diff --git a/config.lua.dist b/config.lua.dist
index 9a2fa89fe..de9f5f785 100644
--- a/config.lua.dist
+++ b/config.lua.dist
@@ -12,6 +12,15 @@ coreDirectory = "data"
 -- NOTE: Will only display logs with level higher or equal the one set.
 logLevel = "info"
 
+--- Toggles the server's maintenance mode.
+-- When enabled, it restricts user access and indicates maintenance operations.
+-- @field [parent=#global] #boolean toggleMaintainMode false by default, set to true to enable maintenance mode.
+toggleMaintainMode = false
+--- Message displayed during maintenance mode.
+-- Should inform the expected downtime or resumption details succinctly.
+-- @field [parent=#global] #string maintainModeMessage an empty string by default, set a custom message if needed.
+maintainModeMessage = ""
+
 -- Combat settings
 -- NOTE: valid values for worldType are: "pvp", "no-pvp" and "pvp-enforced"
 worldType = "pvp"
diff --git a/src/canary_server.cpp b/src/canary_server.cpp
index 3af622c82..da5251605 100644
--- a/src/canary_server.cpp
+++ b/src/canary_server.cpp
@@ -89,8 +89,14 @@ int CanaryServer::run() {
 
 				g_game().start(&serviceManager);
 				g_game().setGameState(GAME_STATE_NORMAL);
-
-				g_webhook().sendMessage("Server is now online", "Server has successfully started.", WEBHOOK_COLOR_ONLINE);
+				if (g_configManager().getBoolean(TOGGLE_MAINTAIN_MODE)) {
+					g_game().setGameState(GAME_STATE_CLOSED);
+					g_logger().warn("Initialized in maintain mode!");
+					g_webhook().sendMessage("Server is now online", "The server is now online. Access is currently restricted to administrators only.", WEBHOOK_COLOR_ONLINE);
+				} else {
+					g_game().setGameState(GAME_STATE_NORMAL);
+					g_webhook().sendMessage("Server is now online", "Server has successfully started.", WEBHOOK_COLOR_ONLINE);
+				}
 
 				loaderStatus = LoaderStatus::LOADED;
 			} catch (FailedToInitializeCanary &err) {
diff --git a/src/config/config_definitions.hpp b/src/config/config_definitions.hpp
index d3bf0b87e..1704b3075 100644
--- a/src/config/config_definitions.hpp
+++ b/src/config/config_definitions.hpp
@@ -82,16 +82,14 @@ enum booleanConfig_t {
 	RESET_SESSIONS_ON_STARTUP,
 	TOGGLE_WHEELSYSTEM,
 	TOGGLE_ATTACK_SPEED_ONFIST,
-
 	VIP_SYSTEM_ENABLED,
 	VIP_AUTOLOOT_VIP_ONLY,
 	VIP_STAY_ONLINE,
-
 	REWARD_CHEST_COLLECT_ENABLED,
 	TOGGLE_MOUNT_IN_PZ,
 	TOGGLE_HOUSE_TRANSFER_ON_SERVER_RESTART,
-
 	TOGGLE_RECEIVE_REWARD,
+	TOGGLE_MAINTAIN_MODE,
 
 	LAST_BOOLEAN_CONFIG
 };
@@ -128,6 +126,7 @@ enum stringConfig_t {
 	FORGE_FIENDISH_INTERVAL_TIME,
 	TIBIADROME_CONCOCTION_TICK_TYPE,
 	M_CONST,
+	MAINTAIN_MODE_MESSAGE,
 
 	LAST_STRING_CONFIG
 };
diff --git a/src/config/configmanager.cpp b/src/config/configmanager.cpp
index d0abcc935..baf93d769 100644
--- a/src/config/configmanager.cpp
+++ b/src/config/configmanager.cpp
@@ -99,6 +99,8 @@ bool ConfigManager::load() {
 		boolean[BIND_ONLY_GLOBAL_ADDRESS] = getGlobalBoolean(L, "bindOnlyGlobalAddress", false);
 		boolean[OPTIMIZE_DATABASE] = getGlobalBoolean(L, "startupDatabaseOptimization", true);
 		boolean[TOGGLE_MAP_CUSTOM] = getGlobalBoolean(L, "toggleMapCustom", true);
+		boolean[TOGGLE_MAINTAIN_MODE] = getGlobalBoolean(L, "toggleMaintainMode", false);
+		string[MAINTAIN_MODE_MESSAGE] = getGlobalString(L, "maintainModeMessage", "");
 
 		string[IP] = getGlobalString(L, "ip", "127.0.0.1");
 		string[MAP_NAME] = getGlobalString(L, "mapName", "canary");
diff --git a/src/creatures/combat/combat.cpp b/src/creatures/combat/combat.cpp
index 38f2c5de2..9a80ad55c 100644
--- a/src/creatures/combat/combat.cpp
+++ b/src/creatures/combat/combat.cpp
@@ -1311,7 +1311,7 @@ std::vector<std::pair<Position, std::vector<uint32_t>>> Combat::pickChainTargets
 
 	std::vector<std::pair<Position, std::vector<uint32_t>>> resultMap;
 	std::vector<std::shared_ptr<Creature>> targets;
-	std::set<uint32_t> visited;
+	phmap::flat_hash_set<uint32_t> visited;
 
 	if (initialTarget && initialTarget != caster) {
 		targets.push_back(initialTarget);
diff --git a/src/creatures/creature.cpp b/src/creatures/creature.cpp
index 7058753ac..c29fe9067 100644
--- a/src/creatures/creature.cpp
+++ b/src/creatures/creature.cpp
@@ -142,10 +142,8 @@ void Creature::onThink(uint32_t interval) {
 	};
 
 	if (isUpdatingPath) {
-		g_dispatcher().asyncEvent([self = getCreature(), onThink = std::move(onThink)] {
-			self->isUpdatingPath = false;
-			self->goToFollowCreature_async(onThink);
-		});
+		isUpdatingPath = false;
+		goToFollowCreature_async(onThink);
 		return;
 	}
 
@@ -433,9 +431,9 @@ void Creature::checkSummonMove(const Position &newPos, bool teleportSummon) {
 	if (hasSummons()) {
 		std::vector<std::shared_ptr<Creature>> despawnMonsterList;
 		for (const auto &summon : getSummons()) {
-			const Position &pos = summon->getPosition();
-			std::shared_ptr<Monster> monster = summon->getMonster();
-			auto tile = getTile();
+			const auto &pos = summon->getPosition();
+			const auto &monster = summon->getMonster();
+			const auto &tile = getTile();
 			bool protectionZoneCheck = tile ? tile->hasFlag(TILESTATE_PROTECTIONZONE) : false;
 			// Check if any of our summons is out of range (+/- 0 floors or 15 tiles away)
 			bool checkSummonDist = Position::getDistanceZ(newPos, pos) > 0 || (std::max<int32_t>(Position::getDistanceX(newPos, pos), Position::getDistanceY(newPos, pos)) > 15);
@@ -443,12 +441,12 @@ void Creature::checkSummonMove(const Position &newPos, bool teleportSummon) {
 			bool checkRemoveDist = Position::getDistanceZ(newPos, pos) > 2 || (std::max<int32_t>(Position::getDistanceX(newPos, pos), Position::getDistanceY(newPos, pos)) > 30);
 
 			if (monster && monster->isFamiliar() && checkSummonDist || teleportSummon && !protectionZoneCheck && checkSummonDist) {
-				auto creatureMaster = summon->getMaster();
+				const auto &creatureMaster = summon->getMaster();
 				if (!creatureMaster) {
 					continue;
 				}
 
-				if (std::shared_ptr<Tile> masterTile = creatureMaster->getTile()) {
+				if (const auto &masterTile = creatureMaster->getTile()) {
 					if (masterTile->hasFlag(TILESTATE_TELEPORT)) {
 						g_logger().warn("[{}] cannot teleport summon, position has teleport. {}", __FUNCTION__, creatureMaster->getPosition().toString());
 					} else {
@@ -463,7 +461,7 @@ void Creature::checkSummonMove(const Position &newPos, bool teleportSummon) {
 			}
 		}
 
-		for (std::shared_ptr<Creature> despawnCreature : despawnMonsterList) {
+		for (const auto &despawnCreature : despawnMonsterList) {
 			if (!despawnMonsterList.empty()) {
 				g_game().removeCreature(despawnCreature, true);
 			}
@@ -632,6 +630,14 @@ void Creature::onCreatureMove(const std::shared_ptr<Creature> &creature, const s
 void Creature::onDeath() {
 	bool lastHitUnjustified = false;
 	bool mostDamageUnjustified = false;
+	std::shared_ptr<Creature> lastHitCreature = g_game().getCreatureByID(lastHitCreatureId);
+	std::shared_ptr<Creature> lastHitCreatureMaster;
+	if (lastHitCreature) {
+		lastHitUnjustified = lastHitCreature->onKilledCreature(static_self_cast<Creature>(), true);
+		lastHitCreatureMaster = lastHitCreature->getMaster();
+	} else {
+		lastHitCreatureMaster = nullptr;
+	}
 
 	std::shared_ptr<Creature> mostDamageCreature = nullptr;
 
@@ -673,15 +679,11 @@ void Creature::onDeath() {
 		it.first->onGainExperience(it.second, getCreature());
 	}
 
-	std::shared_ptr<Creature> mostDamageCreatureMaster = nullptr;
-	if (mostDamageCreature) {
-		mostDamageCreatureMaster = mostDamageCreature->getMaster();
-		mostDamageUnjustified = mostDamageCreature->onKilledCreature(getCreature(), false);
-	}
-
-	std::shared_ptr<Creature> lastHitCreature = g_game().getCreatureByID(lastHitCreatureId);
-	if (lastHitCreature && lastHitCreature != mostDamageCreature && lastHitCreature != mostDamageCreatureMaster) {
-		lastHitUnjustified = lastHitCreature->onKilledCreature(getCreature(), true);
+	if (mostDamageCreature && mostDamageCreature != lastHitCreature && mostDamageCreature != lastHitCreatureMaster) {
+		auto mostDamageCreatureMaster = mostDamageCreature->getMaster();
+		if (lastHitCreature != mostDamageCreatureMaster && (lastHitCreatureMaster == nullptr || mostDamageCreatureMaster != lastHitCreatureMaster)) {
+			mostDamageUnjustified = mostDamageCreature->onKilledCreature(static_self_cast<Creature>(), false);
+		}
 	}
 
 	bool droppedCorpse = dropCorpse(lastHitCreature, mostDamageCreature, lastHitUnjustified, mostDamageUnjustified);
@@ -1245,13 +1247,16 @@ bool Creature::setMaster(std::shared_ptr<Creature> newMaster, bool reloadCreatur
 		g_game().reloadCreature(self);
 	}
 	if (newMaster) {
-		newMaster->m_summons.insert(self);
+		newMaster->m_summons.emplace_back(self);
 	}
 
 	m_master = newMaster;
 
 	if (oldMaster) {
-		oldMaster->m_summons.erase(self);
+		const auto &it = std::ranges::find(oldMaster->m_summons, self);
+		if (it != oldMaster->m_summons.end()) {
+			oldMaster->m_summons.erase(it);
+		}
 	}
 	return true;
 }
@@ -1798,9 +1803,8 @@ void Creature::setIncreasePercent(CombatType_t combat, int32_t value) {
 	}
 }
 
-phmap::flat_hash_set<std::shared_ptr<Zone>> Creature::getZones() {
-	auto tile = getTile();
-	if (tile) {
+std::unordered_set<std::shared_ptr<Zone>> Creature::getZones() {
+	if (const auto &tile = getTile()) {
 		return tile->getZones();
 	}
 	return {};
diff --git a/src/creatures/creature.hpp b/src/creatures/creature.hpp
index 5e03e33d7..e6e8e005e 100644
--- a/src/creatures/creature.hpp
+++ b/src/creatures/creature.hpp
@@ -267,7 +267,7 @@ class Creature : virtual public Thing, public SharedObject {
 		return ZONE_NORMAL;
 	}
 
-	phmap::flat_hash_set<std::shared_ptr<Zone>> getZones();
+	std::unordered_set<std::shared_ptr<Zone>> getZones();
 
 	// walk functions
 	void startAutoWalk(const std::vector<Direction> &listDir, bool ignoreConditions = false);
@@ -341,7 +341,7 @@ class Creature : virtual public Thing, public SharedObject {
 		return m_master.lock();
 	}
 
-	const phmap::flat_hash_set<std::shared_ptr<Creature>> &getSummons() const {
+	const auto &getSummons() const {
 		return m_summons;
 	}
 
@@ -666,7 +666,7 @@ class Creature : virtual public Thing, public SharedObject {
 
 	CountMap damageMap;
 
-	phmap::flat_hash_set<std::shared_ptr<Creature>> m_summons;
+	std::vector<std::shared_ptr<Creature>> m_summons;
 	CreatureEventList eventsList;
 	ConditionList conditions;
 
diff --git a/src/creatures/monsters/monster.hpp b/src/creatures/monsters/monster.hpp
index e6178a4f7..29182fe68 100644
--- a/src/creatures/monsters/monster.hpp
+++ b/src/creatures/monsters/monster.hpp
@@ -17,7 +17,6 @@ class Creature;
 class Game;
 class Spawn;
 
-using CreatureHashSet = phmap::flat_hash_set<std::shared_ptr<Creature>>;
 using CreatureList = std::list<std::shared_ptr<Creature>>;
 
 using CreatureWeakHashMap = phmap::flat_hash_map<uint32_t, std::weak_ptr<Creature>>;
@@ -99,7 +98,7 @@ class Monster final : public Creature {
 		if (master && master->getMonster()) {
 			return master->getMonster()->isEnemyFaction(faction);
 		}
-		return mType->info.enemyFactions.empty() ? false : mType->info.enemyFactions.find(faction) != mType->info.enemyFactions.end();
+		return mType->info.enemyFactions.empty() ? false : mType->info.enemyFactions.contains(faction);
 	}
 
 	bool isPushable() override {
@@ -204,17 +203,19 @@ class Monster final : public Creature {
 		}
 		return list;
 	}
-	CreatureHashSet getFriendList() {
-		CreatureHashSet set;
+
+	std::vector<std::shared_ptr<Creature>> getFriendList() {
+		std::vector<std::shared_ptr<Creature>> list;
+
 		for (auto it = friendList.begin(); it != friendList.end();) {
 			if (auto friendCreature = it->second.lock()) {
-				set.insert(friendCreature);
+				list.emplace_back(friendCreature);
 				++it;
 			} else {
 				it = friendList.erase(it);
 			}
 		}
-		return set;
+		return list;
 	}
 
 	bool isTarget(std::shared_ptr<Creature> creature);
diff --git a/src/creatures/monsters/monsters.hpp b/src/creatures/monsters/monsters.hpp
index e0cc79b88..a4723fcaa 100644
--- a/src/creatures/monsters/monsters.hpp
+++ b/src/creatures/monsters/monsters.hpp
@@ -136,7 +136,7 @@ class MonsterType {
 		bool targetPreferMaster = false;
 
 		Faction_t faction = FACTION_DEFAULT;
-		phmap::flat_hash_set<Faction_t> enemyFactions;
+		stdext::vector_set<Faction_t> enemyFactions;
 
 		bool canPushItems = false;
 		bool canPushCreatures = false;
diff --git a/src/creatures/npcs/npc.cpp b/src/creatures/npcs/npc.cpp
index 2df46c285..431d3113c 100644
--- a/src/creatures/npcs/npc.cpp
+++ b/src/creatures/npcs/npc.cpp
@@ -151,7 +151,7 @@ void Npc::onPlayerAppear(std::shared_ptr<Player> player) {
 	if (player->hasFlag(PlayerFlags_t::IgnoredByNpcs) || playerSpectators.contains(player)) {
 		return;
 	}
-	playerSpectators.emplace_back(player);
+	playerSpectators.emplace(player);
 	manageIdle();
 }
 
@@ -531,7 +531,7 @@ void Npc::onThinkWalk(uint32_t interval) {
 
 void Npc::onCreatureWalk() {
 	Creature::onCreatureWalk();
-	playerSpectators.erase_if([this](const auto &creature) { return !this->canSee(creature->getPosition()); });
+	phmap::erase_if(playerSpectators, [this](const auto &creature) { return !this->canSee(creature->getPosition()); });
 }
 
 void Npc::onPlacedCreature() {
@@ -542,7 +542,7 @@ void Npc::loadPlayerSpectators() {
 	auto spec = Spectators().find<Player>(position, true);
 	for (const auto &creature : spec) {
 		if (!creature->getPlayer()->hasFlag(PlayerFlags_t::IgnoredByNpcs)) {
-			playerSpectators.emplace_back(creature->getPlayer());
+			playerSpectators.emplace(creature->getPlayer());
 		}
 	}
 }
diff --git a/src/creatures/npcs/npc.hpp b/src/creatures/npcs/npc.hpp
index 38cd9840a..993934374 100644
--- a/src/creatures/npcs/npc.hpp
+++ b/src/creatures/npcs/npc.hpp
@@ -188,7 +188,7 @@ class Npc final : public Creature {
 
 	bool ignoreHeight;
 
-	stdext::vector_set<std::shared_ptr<Player>> playerSpectators;
+	phmap::flat_hash_set<std::shared_ptr<Player>> playerSpectators;
 	Position masterPos;
 
 	friend class LuaScriptInterface;
diff --git a/src/creatures/players/player.cpp b/src/creatures/players/player.cpp
index 1178a666e..d26952bc5 100644
--- a/src/creatures/players/player.cpp
+++ b/src/creatures/players/player.cpp
@@ -484,54 +484,48 @@ uint32_t Player::getClientIcons() {
 }
 
 void Player::addMonsterToCyclopediaTrackerList(const std::shared_ptr<MonsterType> mtype, bool isBoss, bool reloadClient /* = false */) {
-	if (client) {
-		uint16_t raceId = mtype ? mtype->info.raceid : 0;
-		// Bostiary tracker logic
-		if (isBoss) {
-			m_bosstiaryMonsterTracker.insert(mtype);
-			if (reloadClient && raceId != 0) {
+	if (!client) {
+		return;
+	}
+
+	const uint16_t raceId = mtype ? mtype->info.raceid : 0;
+	auto &tracker = isBoss ? m_bosstiaryMonsterTracker : m_bestiaryMonsterTracker;
+	if (tracker.emplace(mtype).second) {
+		if (reloadClient && raceId != 0) {
+			if (isBoss) {
 				client->parseSendBosstiary();
+			} else {
+				client->sendBestiaryEntryChanged(raceId);
 			}
-			client->refreshCyclopediaMonsterTracker(m_bosstiaryMonsterTracker, true);
-			return;
 		}
 
-		// Bestiary tracker logic
-		m_bestiaryMonsterTracker.insert(mtype);
-		if (reloadClient && raceId != 0) {
-			client->sendBestiaryEntryChanged(raceId);
-		}
-		client->refreshCyclopediaMonsterTracker(m_bestiaryMonsterTracker, false);
+		client->refreshCyclopediaMonsterTracker(tracker, isBoss);
 	}
 }
 
 void Player::removeMonsterFromCyclopediaTrackerList(std::shared_ptr<MonsterType> mtype, bool isBoss, bool reloadClient /* = false */) {
-	if (client) {
-		uint16_t raceId = mtype ? mtype->info.raceid : 0;
-		// Bostiary tracker logic
-		if (isBoss) {
-			m_bosstiaryMonsterTracker.erase(mtype);
-			if (reloadClient && raceId != 0) {
+	if (!client) {
+		return;
+	}
+
+	const uint16_t raceId = mtype ? mtype->info.raceid : 0;
+	auto &tracker = isBoss ? m_bosstiaryMonsterTracker : m_bestiaryMonsterTracker;
+
+	if (tracker.erase(mtype) > 0) {
+		if (reloadClient && raceId != 0) {
+			if (isBoss) {
 				client->parseSendBosstiary();
+			} else {
+				client->sendBestiaryEntryChanged(raceId);
 			}
-			client->refreshCyclopediaMonsterTracker(m_bosstiaryMonsterTracker, true);
-			return;
 		}
 
-		// Bestiary tracker logic
-		m_bestiaryMonsterTracker.erase(mtype);
-		if (reloadClient && raceId != 0) {
-			client->sendBestiaryEntryChanged(raceId);
-		}
-		client->refreshCyclopediaMonsterTracker(m_bestiaryMonsterTracker, false);
+		client->refreshCyclopediaMonsterTracker(tracker, isBoss);
 	}
 }
 
-bool Player::isBossOnBosstiaryTracker(const std::shared_ptr<MonsterType> monsterType) const {
-	if (!monsterType) {
-		return false;
-	}
-	return m_bosstiaryMonsterTracker.contains(monsterType);
+bool Player::isBossOnBosstiaryTracker(const std::shared_ptr<MonsterType> &monsterType) const {
+	return monsterType ? m_bosstiaryMonsterTracker.contains(monsterType) : false;
 }
 
 void Player::updateInventoryWeight() {
@@ -2925,7 +2919,7 @@ void Player::removePlayer(bool displayEffect, bool forced /*= true*/) {
 	}
 }
 
-void Player::notifyStatusChange(std::shared_ptr<Player> loginPlayer, VipStatus_t status, bool message) {
+void Player::notifyStatusChange(std::shared_ptr<Player> loginPlayer, VipStatus_t status, bool message) const {
 	if (!client) {
 		return;
 	}
@@ -2989,7 +2983,7 @@ bool Player::addVIPInternal(uint32_t vipGuid) {
 	return VIPList.insert(vipGuid).second;
 }
 
-bool Player::editVIP(uint32_t vipGuid, const std::string &description, uint32_t icon, bool notify) {
+bool Player::editVIP(uint32_t vipGuid, const std::string &description, uint32_t icon, bool notify) const {
 	auto it = VIPList.find(vipGuid);
 	if (it == VIPList.end()) {
 		return false; // player is not in VIP
diff --git a/src/creatures/players/player.hpp b/src/creatures/players/player.hpp
index 2a32a838c..418f8659e 100644
--- a/src/creatures/players/player.hpp
+++ b/src/creatures/players/player.hpp
@@ -304,7 +304,7 @@ class Player final : public Creature, public Cylinder, public Bankable {
 		return guildWarVector;
 	}
 
-	const phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> &getCyclopediaMonsterTrackerSet(bool isBoss) const {
+	const std::unordered_set<std::shared_ptr<MonsterType>> &getCyclopediaMonsterTrackerSet(bool isBoss) const {
 		return isBoss ? m_bosstiaryMonsterTracker : m_bestiaryMonsterTracker;
 	}
 
@@ -318,17 +318,17 @@ class Player final : public Creature, public Cylinder, public Bankable {
 		}
 	}
 
-	void refreshCyclopediaMonsterTracker(bool isBoss = false) const {
+	void refreshCyclopediaMonsterTracker(bool isBoss = false) {
 		refreshCyclopediaMonsterTracker(getCyclopediaMonsterTrackerSet(isBoss), isBoss);
 	}
 
-	void refreshCyclopediaMonsterTracker(const phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> &trackerList, bool isBoss) const {
+	void refreshCyclopediaMonsterTracker(const std::unordered_set<std::shared_ptr<MonsterType>> &trackerList, bool isBoss) const {
 		if (client) {
 			client->refreshCyclopediaMonsterTracker(trackerList, isBoss);
 		}
 	}
 
-	bool isBossOnBosstiaryTracker(const std::shared_ptr<MonsterType> monsterType) const;
+	bool isBossOnBosstiaryTracker(const std::shared_ptr<MonsterType> &monsterType) const;
 
 	Vocation* getVocation() const {
 		return vocation;
@@ -804,11 +804,11 @@ class Player final : public Creature, public Cylinder, public Bankable {
 	}
 
 	// V.I.P. functions
-	void notifyStatusChange(std::shared_ptr<Player> player, VipStatus_t status, bool message = true);
+	void notifyStatusChange(std::shared_ptr<Player> player, VipStatus_t status, bool message = true) const;
 	bool removeVIP(uint32_t vipGuid);
 	bool addVIP(uint32_t vipGuid, const std::string &vipName, VipStatus_t status);
 	bool addVIPInternal(uint32_t vipGuid);
-	bool editVIP(uint32_t vipGuid, const std::string &description, uint32_t icon, bool notify);
+	bool editVIP(uint32_t vipGuid, const std::string &description, uint32_t icon, bool notify) const;
 
 	// follow functions
 	bool setFollowCreature(std::shared_ptr<Creature> creature) override;
@@ -2502,7 +2502,7 @@ class Player final : public Creature, public Cylinder, public Bankable {
 	}
 
 	bool checkAutoLoot() const {
-		const bool autoLoot = g_configManager().getBoolean(AUTOLOOT) && getStorageValue(STORAGEVALUE_AUTO_LOOT) != 0;
+		const bool autoLoot = g_configManager().getBoolean(AUTOLOOT) && getStorageValue(STORAGEVALUE_AUTO_LOOT) > 0;
 		if (g_configManager().getBoolean(VIP_SYSTEM_ENABLED) && g_configManager().getBoolean(VIP_AUTOLOOT_VIP_ONLY)) {
 			return autoLoot && isVip();
 		}
@@ -2609,7 +2609,6 @@ class Player final : public Creature, public Cylinder, public Bankable {
 	bool onKilledMonster(const std::shared_ptr<Monster> &target, bool lastHit);
 
 	phmap::flat_hash_set<uint32_t> attackedSet;
-
 	phmap::flat_hash_set<uint32_t> VIPList;
 
 	std::map<uint8_t, OpenContainer> openContainers;
@@ -2646,8 +2645,8 @@ class Player final : public Creature, public Cylinder, public Bankable {
 	// TODO: This variable is only temporarily used when logging in, get rid of it somehow.
 	std::forward_list<std::shared_ptr<Condition>> storedConditionList;
 
-	phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> m_bestiaryMonsterTracker;
-	phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> m_bosstiaryMonsterTracker;
+	std::unordered_set<std::shared_ptr<MonsterType>> m_bestiaryMonsterTracker;
+	std::unordered_set<std::shared_ptr<MonsterType>> m_bosstiaryMonsterTracker;
 
 	std::string name;
 	std::string guildNick;
diff --git a/src/game/bank/bank.cpp b/src/game/bank/bank.cpp
index 63952e917..f1a700388 100644
--- a/src/game/bank/bank.cpp
+++ b/src/game/bank/bank.cpp
@@ -97,7 +97,7 @@ bool Bank::transferTo(const std::shared_ptr<Bank> destination, uint64_t amount)
 		return false;
 	}
 	if (destinationBankable->getPlayer() != nullptr) {
-		auto player = bankable->getPlayer();
+		auto player = destinationBankable->getPlayer();
 		auto name = asLowerCaseString(player->getName());
 		replaceString(name, " ", "");
 		if (deniedNames.contains(name)) {
diff --git a/src/game/game.cpp b/src/game/game.cpp
index a01ac60bf..64cbf5cec 100644
--- a/src/game/game.cpp
+++ b/src/game/game.cpp
@@ -7617,8 +7617,7 @@ void Game::updatePlayerHelpers(std::shared_ptr<Player> player) {
 		return;
 	}
 
-	uint16_t helpers = player->getHelpers();
-
+	const uint16_t helpers = player->getHelpers();
 	for (const auto &spectator : Spectators().find<Player>(player->getPosition(), true)) {
 		spectator->getPlayer()->sendCreatureHelpers(player->getID(), helpers);
 	}
@@ -9925,25 +9924,28 @@ void Game::setTransferPlayerHouseItems(uint32_t houseId, uint32_t playerId) {
 }
 
 template <typename T>
-phmap::parallel_flat_hash_set<T> setDifference(const phmap::flat_hash_set<T> &setA, const phmap::flat_hash_set<T> &setB) {
-	phmap::parallel_flat_hash_set<T> setResult;
+std::vector<T> setDifference(const std::unordered_set<T> &setA, const std::unordered_set<T> &setB) {
+	std::vector<T> setResult;
+	setResult.reserve(setA.size());
+
 	for (const auto &elem : setA) {
-		if (setB.find(elem) == setB.end()) {
-			setResult.insert(elem);
+		if (!setB.contains(elem)) {
+			setResult.emplace_back(elem);
 		}
 	}
+
 	return setResult;
 }
 
-ReturnValue Game::beforeCreatureZoneChange(std::shared_ptr<Creature> creature, const phmap::flat_hash_set<std::shared_ptr<Zone>> &fromZones, const phmap::flat_hash_set<std::shared_ptr<Zone>> &toZones, bool force /* = false*/) const {
+ReturnValue Game::beforeCreatureZoneChange(std::shared_ptr<Creature> creature, const std::unordered_set<std::shared_ptr<Zone>> &fromZones, const std::unordered_set<std::shared_ptr<Zone>> &toZones, bool force /* = false*/) const {
 	if (!creature) {
 		return RETURNVALUE_NOTPOSSIBLE;
 	}
 
 	// fromZones - toZones = zones that creature left
-	auto zonesLeaving = setDifference(fromZones, toZones);
+	const auto &zonesLeaving = setDifference(fromZones, toZones);
 	// toZones - fromZones = zones that creature entered
-	auto zonesEntering = setDifference(toZones, fromZones);
+	const auto &zonesEntering = setDifference(toZones, fromZones);
 
 	if (zonesLeaving.empty() && zonesEntering.empty()) {
 		return RETURNVALUE_NOERROR;
@@ -9965,15 +9967,15 @@ ReturnValue Game::beforeCreatureZoneChange(std::shared_ptr<Creature> creature, c
 	return RETURNVALUE_NOERROR;
 }
 
-void Game::afterCreatureZoneChange(std::shared_ptr<Creature> creature, const phmap::flat_hash_set<std::shared_ptr<Zone>> &fromZones, const phmap::flat_hash_set<std::shared_ptr<Zone>> &toZones) const {
+void Game::afterCreatureZoneChange(std::shared_ptr<Creature> creature, const std::unordered_set<std::shared_ptr<Zone>> &fromZones, const std::unordered_set<std::shared_ptr<Zone>> &toZones) const {
 	if (!creature) {
 		return;
 	}
 
 	// fromZones - toZones = zones that creature left
-	auto zonesLeaving = setDifference(fromZones, toZones);
+	const auto &zonesLeaving = setDifference(fromZones, toZones);
 	// toZones - fromZones = zones that creature entered
-	auto zonesEntering = setDifference(toZones, fromZones);
+	const auto &zonesEntering = setDifference(toZones, fromZones);
 
 	for (const auto &zone : zonesLeaving) {
 		zone->creatureRemoved(creature);
diff --git a/src/game/game.hpp b/src/game/game.hpp
index 2b30a31d2..9dbbbca9f 100644
--- a/src/game/game.hpp
+++ b/src/game/game.hpp
@@ -557,7 +557,7 @@ class Game {
 	Raids raids;
 	Canary::protobuf::appearances::Appearances appearances;
 
-	phmap::flat_hash_set<std::shared_ptr<Tile>> getTilesToClean() const {
+	auto getTilesToClean() const {
 		return tilesToClean;
 	}
 	void addTileToClean(std::shared_ptr<Tile> tile) {
@@ -599,11 +599,11 @@ class Game {
 		mapLuaItemsStored[position] = itemId;
 	}
 
-	std::set<uint32_t> getFiendishMonsters() const {
+	auto getFiendishMonsters() const {
 		return fiendishMonsters;
 	}
 
-	std::set<uint32_t> getInfluencedMonsters() const {
+	auto getInfluencedMonsters() const {
 		return influencedMonsters;
 	}
 
@@ -673,8 +673,8 @@ class Game {
 	 */
 	bool tryRetrieveStashItems(std::shared_ptr<Player> player, std::shared_ptr<Item> item);
 
-	ReturnValue beforeCreatureZoneChange(std::shared_ptr<Creature> creature, const phmap::flat_hash_set<std::shared_ptr<Zone>> &fromZones, const phmap::flat_hash_set<std::shared_ptr<Zone>> &toZones, bool force = false) const;
-	void afterCreatureZoneChange(std::shared_ptr<Creature> creature, const phmap::flat_hash_set<std::shared_ptr<Zone>> &fromZones, const phmap::flat_hash_set<std::shared_ptr<Zone>> &toZones) const;
+	ReturnValue beforeCreatureZoneChange(std::shared_ptr<Creature> creature, const std::unordered_set<std::shared_ptr<Zone>> &fromZones, const std::unordered_set<std::shared_ptr<Zone>> &toZones, bool force = false) const;
+	void afterCreatureZoneChange(std::shared_ptr<Creature> creature, const std::unordered_set<std::shared_ptr<Zone>> &fromZones, const std::unordered_set<std::shared_ptr<Zone>> &toZones) const;
 
 	std::unique_ptr<IOWheel> &getIOWheel();
 	const std::unique_ptr<IOWheel> &getIOWheel() const;
@@ -684,8 +684,8 @@ class Game {
 
 private:
 	std::map<uint32_t, int32_t> forgeMonsterEventIds;
-	std::set<uint32_t> fiendishMonsters;
-	std::set<uint32_t> influencedMonsters;
+	std::unordered_set<uint32_t> fiendishMonsters;
+	std::unordered_set<uint32_t> influencedMonsters;
 	void checkImbuements();
 	bool playerSaySpell(std::shared_ptr<Player> player, SpeakClasses type, const std::string &text);
 	void playerWhisper(std::shared_ptr<Player> player, const std::string &text);
@@ -822,7 +822,7 @@ class Game {
 
 	std::map<uint32_t, std::shared_ptr<BedItem>> bedSleepersMap;
 
-	phmap::flat_hash_set<std::shared_ptr<Tile>> tilesToClean;
+	std::unordered_set<std::shared_ptr<Tile>> tilesToClean;
 
 	ModalWindow offlineTrainingWindow { std::numeric_limits<uint32_t>::max(), "Choose a Skill", "Please choose a skill:" };
 
diff --git a/src/game/scheduling/events_scheduler.cpp b/src/game/scheduling/events_scheduler.cpp
index d5c71378f..fc41f2c8b 100644
--- a/src/game/scheduling/events_scheduler.cpp
+++ b/src/game/scheduling/events_scheduler.cpp
@@ -28,7 +28,7 @@ bool EventsScheduler::loadScheduleEventFromXml() {
 
 	// Keep track of loaded scripts to check for duplicates
 	int count = 0;
-	std::set<std::string_view, std::less<>> loadedScripts;
+	phmap::flat_hash_set<std::string_view> loadedScripts;
 	std::map<std::string, EventRates> eventsOnSameDay;
 	for (const auto &eventNode : doc.child("events").children()) {
 		std::string eventScript = eventNode.attribute("script").as_string();
diff --git a/src/game/zones/zone.hpp b/src/game/zones/zone.hpp
index 4a0c03180..91fa6f25e 100644
--- a/src/game/zones/zone.hpp
+++ b/src/game/zones/zone.hpp
@@ -9,7 +9,6 @@
 
 #pragma once
 
-#include <unordered_set>
 #include "game/movement/position.hpp"
 #include "items/item.hpp"
 #include "creatures/creature.hpp"
diff --git a/src/io/io_bosstiary.cpp b/src/io/io_bosstiary.cpp
index e4aecee5f..10c4f2f08 100644
--- a/src/io/io_bosstiary.cpp
+++ b/src/io/io_bosstiary.cpp
@@ -234,14 +234,13 @@ uint32_t IOBosstiary::calculateBossPoints(uint16_t lootBonus) const {
 	return static_cast<uint32_t>((2.5 * lootBonus * lootBonus) - (477.5 * lootBonus) + 24000);
 }
 
-phmap::parallel_flat_hash_set<uint16_t> IOBosstiary::getBosstiaryFinished(std::shared_ptr<Player> player, uint8_t level /* = 1*/) const {
-	phmap::parallel_flat_hash_set<uint16_t> unlockedMonsters;
+std::vector<uint16_t> IOBosstiary::getBosstiaryFinished(const std::shared_ptr<Player> &player, uint8_t level /* = 1*/) const {
 	if (!player) {
-		return unlockedMonsters;
+		return {};
 	}
 
-	for (std::map<uint16_t, std::string> bossesMap = getBosstiaryMap();
-		 const auto &[bossId, bossName] : bossesMap) {
+	stdext::vector_set<uint16_t> unlockedMonsters;
+	for (const auto &[bossId, bossName] : getBosstiaryMap()) {
 		uint32_t bossKills = player->getBestiaryKillCount(bossId);
 		if (bossKills == 0) {
 			continue;
@@ -258,14 +257,14 @@ phmap::parallel_flat_hash_set<uint16_t> IOBosstiary::getBosstiaryFinished(std::s
 			const std::vector<LevelInfo> &infoForCurrentRace = it->second;
 			auto levelKills = infoForCurrentRace.at(level - 1).kills;
 			if (bossKills >= levelKills) {
-				unlockedMonsters.insert(bossId);
+				unlockedMonsters.emplace(bossId);
 			}
 		} else {
 			g_logger().warn("[{}] boss with id {} and name {} not found in bossRace", __FUNCTION__, bossId, bossName);
 		}
 	}
 
-	return unlockedMonsters;
+	return unlockedMonsters.data();
 }
 
 uint8_t IOBosstiary::getBossCurrentLevel(std::shared_ptr<Player> player, uint16_t bossId) const {
diff --git a/src/io/io_bosstiary.hpp b/src/io/io_bosstiary.hpp
index a253be3b4..b491247b2 100644
--- a/src/io/io_bosstiary.hpp
+++ b/src/io/io_bosstiary.hpp
@@ -63,7 +63,7 @@ class IOBosstiary {
 	void addBosstiaryKill(std::shared_ptr<Player> player, const std::shared_ptr<MonsterType> mtype, uint32_t amount = 1) const;
 	uint16_t calculateLootBonus(uint32_t bossPoints) const;
 	uint32_t calculateBossPoints(uint16_t lootBonus) const;
-	phmap::parallel_flat_hash_set<uint16_t> getBosstiaryFinished(std::shared_ptr<Player> player, uint8_t level = 1) const;
+	std::vector<uint16_t> getBosstiaryFinished(const std::shared_ptr<Player> &player, uint8_t level = 1) const;
 	uint8_t getBossCurrentLevel(std::shared_ptr<Player> player, uint16_t bossId) const;
 	uint32_t calculteRemoveBoss(uint8_t removeTimes) const;
 	const std::vector<LevelInfo> &getBossRaceKillStages(BosstiaryRarity_t race) const;
diff --git a/src/io/iobestiary.cpp b/src/io/iobestiary.cpp
index c9fb933bc..2f66c53ad 100644
--- a/src/io/iobestiary.cpp
+++ b/src/io/iobestiary.cpp
@@ -227,7 +227,6 @@ void IOBestiary::addBestiaryKill(std::shared_ptr<Player> player, const std::shar
 		(curCount < mtype->info.bestiaryFirstUnlock && (curCount + amount) >= mtype->info.bestiaryFirstUnlock) || // First kill stage reached
 		(curCount < mtype->info.bestiarySecondUnlock && (curCount + amount) >= mtype->info.bestiarySecondUnlock) || // Second kill stage reached
 		(curCount < mtype->info.bestiaryToUnlock && (curCount + amount) >= mtype->info.bestiaryToUnlock)) { // Final kill stage reached
-
 		ss << "You unlocked details for the creature '" << mtype->name << "'";
 		player->sendTextMessage(MESSAGE_STATUS, ss.str());
 		player->sendBestiaryEntryChanged(raceid);
@@ -305,7 +304,6 @@ void IOBestiary::sendBuyCharmRune(std::shared_ptr<Player> player, charmRune_t ru
 
 		int32_t value = bitToggle(player->getUnlockedRunesBit(), charm, true);
 		player->setUnlockedRunesBit(value);
-
 	} else if (action == 1) {
 		std::list<charmRune_t> usedRunes = getCharmUsedRuneBitAll(player);
 		uint16_t limitRunes = 0;
@@ -396,18 +394,21 @@ std::map<uint16_t, uint32_t> IOBestiary::getBestiaryKillCountByMonsterIDs(std::s
 	return raceMonsters;
 }
 
-phmap::parallel_flat_hash_set<uint16_t> IOBestiary::getBestiaryFinished(std::shared_ptr<Player> player) const {
-	phmap::parallel_flat_hash_set<uint16_t> finishedMonsters;
-	auto bestiaryMap = g_game().getBestiaryList();
+std::vector<uint16_t> IOBestiary::getBestiaryFinished(const std::shared_ptr<Player> &player) const {
+	const auto &bestiaryMap = g_game().getBestiaryList();
+
+	stdext::vector_set<uint16_t> finishedMonsters;
+	finishedMonsters.reserve(bestiaryMap.size());
 
 	for (const auto &[monsterTypeRaceId, monsterTypeName] : bestiaryMap) {
-		uint32_t thisKilled = player->getBestiaryKillCount(monsterTypeRaceId);
-		auto mtype = g_monsters().getMonsterType(monsterTypeName);
+		const auto &mtype = g_monsters().getMonsterType(monsterTypeName);
+		const uint32_t thisKilled = player->getBestiaryKillCount(monsterTypeRaceId);
+
 		if (mtype && thisKilled >= mtype->info.bestiaryToUnlock) {
 			finishedMonsters.insert(monsterTypeRaceId);
 		}
 	}
-	return finishedMonsters;
+	return finishedMonsters.data();
 }
 
 int8_t IOBestiary::calculateDifficult(uint32_t chance) const {
diff --git a/src/io/iobestiary.hpp b/src/io/iobestiary.hpp
index 26f802dcb..896e00434 100644
--- a/src/io/iobestiary.hpp
+++ b/src/io/iobestiary.hpp
@@ -72,7 +72,7 @@ class IOBestiary {
 	bool hasCharmUnlockedRuneBit(const std::shared_ptr<Charm> charm, int32_t input) const;
 
 	std::list<charmRune_t> getCharmUsedRuneBitAll(std::shared_ptr<Player> player);
-	phmap::parallel_flat_hash_set<uint16_t> getBestiaryFinished(std::shared_ptr<Player> player) const;
+	std::vector<uint16_t> getBestiaryFinished(const std::shared_ptr<Player> &player) const;
 
 	charmRune_t getCharmFromTarget(std::shared_ptr<Player> player, const std::shared_ptr<MonsterType> mtype);
 
diff --git a/src/items/containers/container.cpp b/src/items/containers/container.cpp
index 54ce00ace..af17ce692 100644
--- a/src/items/containers/container.cpp
+++ b/src/items/containers/container.cpp
@@ -278,8 +278,8 @@ std::deque<std::shared_ptr<Item>> Container::getStoreInboxFilteredItems() const
 	return storeInboxFilteredList;
 }
 
-phmap::flat_hash_set<ContainerCategory_t> Container::getStoreInboxValidCategories() const {
-	phmap::flat_hash_set<ContainerCategory_t> validCategories;
+std::vector<ContainerCategory_t> Container::getStoreInboxValidCategories() const {
+	stdext::vector_set<ContainerCategory_t> validCategories;
 	for (const auto &item : itemlist) {
 		auto itemId = item->getID();
 		auto attribute = item->getCustomAttribute("unWrapId");
@@ -297,7 +297,7 @@ phmap::flat_hash_set<ContainerCategory_t> Container::getStoreInboxValidCategorie
 		}
 	}
 
-	return validCategories;
+	return validCategories.data();
 }
 
 std::shared_ptr<Item> Container::getFilteredItemByIndex(size_t index) const {
diff --git a/src/items/containers/container.hpp b/src/items/containers/container.hpp
index 0b014aee5..56d048f3b 100644
--- a/src/items/containers/container.hpp
+++ b/src/items/containers/container.hpp
@@ -109,7 +109,7 @@ class Container : public Item, public Cylinder {
 	bool isStoreInbox() const;
 	bool isStoreInboxFiltered() const;
 	std::deque<std::shared_ptr<Item>> getStoreInboxFilteredItems() const;
-	phmap::flat_hash_set<ContainerCategory_t> getStoreInboxValidCategories() const;
+	std::vector<ContainerCategory_t> getStoreInboxValidCategories() const;
 	std::shared_ptr<Item> getFilteredItemByIndex(size_t index) const;
 	std::shared_ptr<Item> getItemByIndex(size_t index) const;
 	bool isHoldingItem(std::shared_ptr<Item> item);
diff --git a/src/items/tile.cpp b/src/items/tile.cpp
index 44631406f..22c325cfd 100644
--- a/src/items/tile.cpp
+++ b/src/items/tile.cpp
@@ -1800,12 +1800,8 @@ std::shared_ptr<Item> Tile::getDoorItem() const {
 	return nullptr;
 }
 
-phmap::flat_hash_set<std::shared_ptr<Zone>> Tile::getZones() {
-	return zones;
-}
-
 void Tile::addZone(std::shared_ptr<Zone> zone) {
-	zones.insert(zone);
+	zones.emplace(zone);
 	const auto &items = getItemList();
 	if (items) {
 		for (const auto &item : *items) {
@@ -1821,12 +1817,12 @@ void Tile::addZone(std::shared_ptr<Zone> zone) {
 }
 
 void Tile::clearZones() {
-	phmap::flat_hash_set<std::shared_ptr<Zone>> zonesToRemove;
+	std::vector<std::shared_ptr<Zone>> zonesToRemove;
 	for (const auto &zone : zones) {
 		if (zone->isStatic()) {
 			continue;
 		}
-		zonesToRemove.insert(zone);
+		zonesToRemove.emplace_back(zone);
 		const auto &items = getItemList();
 		if (items) {
 			for (const auto &item : *items) {
diff --git a/src/items/tile.hpp b/src/items/tile.hpp
index c54717561..bb10b3091 100644
--- a/src/items/tile.hpp
+++ b/src/items/tile.hpp
@@ -176,7 +176,9 @@ class Tile : public Cylinder, public SharedObject {
 	void addZone(std::shared_ptr<Zone> zone);
 	void clearZones();
 
-	phmap::flat_hash_set<std::shared_ptr<Zone>> getZones();
+	auto getZones() const {
+		return zones;
+	}
 
 	ZoneType_t getZoneType() const {
 		if (hasFlag(TILESTATE_PROTECTIONZONE)) {
@@ -270,7 +272,7 @@ class Tile : public Cylinder, public SharedObject {
 	std::shared_ptr<Item> ground = nullptr;
 	Position tilePos;
 	uint32_t flags = 0;
-	phmap::flat_hash_set<std::shared_ptr<Zone>> zones;
+	std::unordered_set<std::shared_ptr<Zone>> zones;
 };
 
 // Used for walkable tiles, where there is high likeliness of
diff --git a/src/lua/creature/events.cpp b/src/lua/creature/events.cpp
index 176044d66..055394214 100644
--- a/src/lua/creature/events.cpp
+++ b/src/lua/creature/events.cpp
@@ -30,14 +30,14 @@ bool Events::loadFromXml() {
 
 	info = {};
 
-	std::set<std::string> classes;
+	phmap::flat_hash_set<std::string> classes;
 	for (auto eventNode : doc.child("events").children()) {
 		if (!eventNode.attribute("enabled").as_bool()) {
 			continue;
 		}
 
 		const std::string &className = eventNode.attribute("class").as_string();
-		auto res = classes.insert(className);
+		auto res = classes.emplace(className);
 		if (res.second) {
 			const std::string &lowercase = asLowerCaseString(className);
 			const std::string &scriptName = lowercase + ".lua";
diff --git a/src/lua/functions/creatures/monster/loot_functions.cpp b/src/lua/functions/creatures/monster/loot_functions.cpp
index 81e42535f..b23508033 100644
--- a/src/lua/functions/creatures/monster/loot_functions.cpp
+++ b/src/lua/functions/creatures/monster/loot_functions.cpp
@@ -259,7 +259,13 @@ int LootFunctions::luaLootAddChildLoot(lua_State* L) {
 	// loot:addChildLoot(loot)
 	const auto loot = getUserdataShared<Loot>(L, 1);
 	if (loot) {
-		loot->lootBlock.childLoot.push_back(getUserdata<Loot>(L, 2)->lootBlock);
+		const auto childLoot = getUserdata<Loot>(L, 2);
+		if (childLoot) {
+			loot->lootBlock.childLoot.push_back(childLoot->lootBlock);
+			pushBoolean(L, true);
+		} else {
+			pushBoolean(L, false);
+		}
 	} else {
 		lua_pushnil(L);
 	}
diff --git a/src/lua/functions/creatures/monster/monster_functions.cpp b/src/lua/functions/creatures/monster/monster_functions.cpp
index 60e60fe87..e0f702f24 100644
--- a/src/lua/functions/creatures/monster/monster_functions.cpp
+++ b/src/lua/functions/creatures/monster/monster_functions.cpp
@@ -219,11 +219,11 @@ int MonsterFunctions::luaMonsterGetFriendList(lua_State* L) {
 		return 1;
 	}
 
-	const auto friendList = monster->getFriendList();
+	const auto &friendList = monster->getFriendList();
 	lua_createtable(L, friendList.size(), 0);
 
 	int index = 0;
-	for (std::shared_ptr<Creature> creature : friendList) {
+	for (const auto &creature : friendList) {
 		pushUserdata<Creature>(L, creature);
 		setCreatureMetatable(L, -1, creature);
 		lua_rawseti(L, -2, ++index);
diff --git a/src/lua/functions/creatures/monster/monster_type_functions.cpp b/src/lua/functions/creatures/monster/monster_type_functions.cpp
index 0db51998e..146ee7b1a 100644
--- a/src/lua/functions/creatures/monster/monster_type_functions.cpp
+++ b/src/lua/functions/creatures/monster/monster_type_functions.cpp
@@ -426,13 +426,13 @@ int MonsterTypeFunctions::luaMonsterTypeEnemyFactions(lua_State* L) {
 			lua_createtable(L, monsterType->info.enemyFactions.size(), 0);
 			int index = 0;
 
-			for (auto faction : monsterType->info.enemyFactions) {
+			for (const auto &faction : monsterType->info.enemyFactions) {
 				lua_pushnumber(L, faction);
 				lua_rawseti(L, -2, ++index);
 			}
 		} else {
 			Faction_t faction = getNumber<Faction_t>(L, 2);
-			monsterType->info.enemyFactions.emplace(faction);
+			monsterType->info.enemyFactions.insert(faction);
 			pushBoolean(L, true);
 		}
 	} else {
diff --git a/src/lua/functions/creatures/player/player_functions.cpp b/src/lua/functions/creatures/player/player_functions.cpp
index 12e7379a2..7c8934b45 100644
--- a/src/lua/functions/creatures/player/player_functions.cpp
+++ b/src/lua/functions/creatures/player/player_functions.cpp
@@ -328,8 +328,7 @@ int PlayerFunctions::luaPlayerIsMonsterBestiaryUnlocked(lua_State* L) {
 		return 0;
 	}
 
-	for (auto finishedMonsters = g_iobestiary().getBestiaryFinished(player);
-		 uint16_t finishedRaceId : finishedMonsters) {
+	for (uint16_t finishedRaceId : g_iobestiary().getBestiaryFinished(player)) {
 		if (raceId == finishedRaceId) {
 			pushBoolean(L, true);
 			return 1;
diff --git a/src/lua/functions/lua_functions_loader.cpp b/src/lua/functions/lua_functions_loader.cpp
index 0973876c2..bdf7dbb37 100644
--- a/src/lua/functions/lua_functions_loader.cpp
+++ b/src/lua/functions/lua_functions_loader.cpp
@@ -239,11 +239,11 @@ void LuaFunctionsLoader::setMetatable(lua_State* L, int32_t index, const std::st
 }
 
 void LuaFunctionsLoader::setWeakMetatable(lua_State* L, int32_t index, const std::string &name) {
+	static phmap::flat_hash_set<std::string> weakObjectTypes;
 	if (validateDispatcherContext(__FUNCTION__)) {
 		return;
 	}
 
-	static std::set<std::string> weakObjectTypes;
 	const std::string &weakName = name + "_weak";
 
 	auto result = weakObjectTypes.emplace(name);
diff --git a/src/map/house/house.cpp b/src/map/house/house.cpp
index 8bb26bcfb..748e24aee 100644
--- a/src/map/house/house.cpp
+++ b/src/map/house/house.cpp
@@ -163,7 +163,7 @@ void House::updateDoorDescription() const {
 	}
 }
 
-AccessHouseLevel_t House::getHouseAccessLevel(std::shared_ptr<Player> player) {
+AccessHouseLevel_t House::getHouseAccessLevel(std::shared_ptr<Player> player) const {
 	if (!player) {
 		return HOUSE_OWNER;
 	}
@@ -369,10 +369,6 @@ bool House::getAccessList(uint32_t listId, std::string &list) const {
 	return door->getAccessList(list);
 }
 
-bool House::isInvited(std::shared_ptr<Player> player) {
-	return getHouseAccessLevel(player) != HOUSE_NOT_INVITED;
-}
-
 void House::addDoor(std::shared_ptr<Door> door) {
 	doorList.push_back(door);
 	door->setHouse(static_self_cast<House>());
@@ -414,7 +410,7 @@ std::shared_ptr<Door> House::getDoorByPosition(const Position &pos) {
 	return nullptr;
 }
 
-bool House::canEditAccessList(uint32_t listId, std::shared_ptr<Player> player) {
+bool House::canEditAccessList(uint32_t listId, const std::shared_ptr<Player> &player) const {
 	switch (getHouseAccessLevel(player)) {
 		case HOUSE_OWNER:
 			return true;
@@ -602,18 +598,17 @@ void AccessList::addGuildRank(const std::string &name, const std::string &guildN
 	}
 }
 
-bool AccessList::isInList(std::shared_ptr<Player> player) {
+bool AccessList::isInList(std::shared_ptr<Player> player) const {
 	if (allowEveryone) {
 		return true;
 	}
 
-	auto playerIt = playerList.find(player->getGUID());
-	if (playerIt != playerList.end()) {
+	if (playerList.contains(player->getGUID())) {
 		return true;
 	}
 
-	GuildRank_ptr rank = player->getGuildRank();
-	return rank && guildRankList.find(rank->id) != guildRankList.end();
+	const auto &rank = player->getGuildRank();
+	return rank && guildRankList.contains(rank->id);
 }
 
 void AccessList::getList(std::string &retList) const {
@@ -648,7 +643,7 @@ void Door::setHouse(std::shared_ptr<House> newHouse) {
 	}
 }
 
-bool Door::canUse(std::shared_ptr<Player> player) {
+bool Door::canUse(std::shared_ptr<Player> player) const {
 	if (!house) {
 		return true;
 	}
diff --git a/src/map/house/house.hpp b/src/map/house/house.hpp
index 845693e30..2e8427a57 100644
--- a/src/map/house/house.hpp
+++ b/src/map/house/house.hpp
@@ -25,7 +25,7 @@ class AccessList {
 	void addGuild(const std::string &name);
 	void addGuildRank(const std::string &name, const std::string &rankName);
 
-	bool isInList(std::shared_ptr<Player> player);
+	bool isInList(std::shared_ptr<Player> player) const;
 
 	void getList(std::string &list) const;
 
@@ -63,7 +63,7 @@ class Door final : public Item {
 		return getAttribute<uint32_t>(ItemAttribute_t::DOORID);
 	}
 
-	bool canUse(std::shared_ptr<Player> player);
+	bool canUse(std::shared_ptr<Player> player) const;
 
 	void setAccessList(const std::string &textlist);
 	bool getAccessList(std::string &list) const;
@@ -104,16 +104,18 @@ class House : public SharedObject {
 	void addTile(std::shared_ptr<HouseTile> tile);
 	void updateDoorDescription() const;
 
-	bool canEditAccessList(uint32_t listId, std::shared_ptr<Player> player);
+	bool canEditAccessList(uint32_t listId, const std::shared_ptr<Player> &player) const;
 	// listId special = values:
 	// GUEST_LIST = guest list
 	// SUBOWNER_LIST = subowner list
 	void setAccessList(uint32_t listId, const std::string &textlist);
 	bool getAccessList(uint32_t listId, std::string &list) const;
 
-	bool isInvited(std::shared_ptr<Player> player);
+	bool isInvited(const std::shared_ptr<Player> &player) const {
+		return getHouseAccessLevel(player) != HOUSE_NOT_INVITED;
+	}
 
-	AccessHouseLevel_t getHouseAccessLevel(std::shared_ptr<Player> player);
+	AccessHouseLevel_t getHouseAccessLevel(std::shared_ptr<Player> player) const;
 	bool kickPlayer(std::shared_ptr<Player> player, std::shared_ptr<Player> target);
 
 	void setEntryPos(Position pos) {
diff --git a/src/map/map.cpp b/src/map/map.cpp
index 72e867551..3771f5662 100644
--- a/src/map/map.cpp
+++ b/src/map/map.cpp
@@ -325,8 +325,8 @@ void Map::moveCreature(const std::shared_ptr<Creature> &creature, const std::sha
 	Position oldPos = oldTile->getPosition();
 	Position newPos = newTile->getPosition();
 
-	auto fromZones = oldTile->getZones();
-	auto toZones = newTile->getZones();
+	const auto &fromZones = oldTile->getZones();
+	const auto &toZones = newTile->getZones();
 	if (auto ret = g_game().beforeCreatureZoneChange(creature, fromZones, toZones); ret != RETURNVALUE_NOERROR) {
 		return;
 	}
@@ -694,13 +694,13 @@ uint32_t Map::clean() {
 	}
 
 	std::vector<std::shared_ptr<Item>> toRemove;
-	for (auto tile : g_game().getTilesToClean()) {
+	for (const auto &tile : g_game().getTilesToClean()) {
 		if (!tile) {
 			continue;
 		}
-		if (auto items = tile->getItemList()) {
+		if (const auto items = tile->getItemList()) {
 			++tiles;
-			for (auto item : *items) {
+			for (const auto &item : *items) {
 				if (item->isCleanable()) {
 					toRemove.emplace_back(item);
 				}
@@ -708,7 +708,7 @@ uint32_t Map::clean() {
 		}
 	}
 
-	for (auto item : toRemove) {
+	for (const auto &item : toRemove) {
 		g_game().internalRemoveItem(item, -1);
 	}
 
diff --git a/src/map/mapcache.cpp b/src/map/mapcache.cpp
index c39629806..e0e58e5f0 100644
--- a/src/map/mapcache.cpp
+++ b/src/map/mapcache.cpp
@@ -107,6 +107,8 @@ std::shared_ptr<Tile> MapCache::getOrCreateTileFromCache(const std::unique_ptr<F
 		return floor->getTile(x, y);
 	}
 
+	std::unique_lock l(floor->getMutex());
+
 	const uint8_t z = floor->getZ();
 
 	auto map = static_cast<Map*>(this);
diff --git a/src/map/mapcache.hpp b/src/map/mapcache.hpp
index 7dda032b7..6265e979f 100644
--- a/src/map/mapcache.hpp
+++ b/src/map/mapcache.hpp
@@ -86,6 +86,7 @@ struct Floor {
 		z(z) {};
 
 	std::shared_ptr<Tile> getTile(uint16_t x, uint16_t y) const {
+		std::shared_lock sl(mutex);
 		return tiles[x & FLOOR_MASK][y & FLOOR_MASK].first;
 	}
 
@@ -94,6 +95,7 @@ struct Floor {
 	}
 
 	std::shared_ptr<BasicTile> getTileCache(uint16_t x, uint16_t y) const {
+		std::shared_lock sl(mutex);
 		return tiles[x & FLOOR_MASK][y & FLOOR_MASK].second;
 	}
 
@@ -105,8 +107,13 @@ struct Floor {
 		return z;
 	}
 
+	auto &getMutex() const {
+		return mutex;
+	}
+
 private:
 	std::pair<std::shared_ptr<Tile>, std::shared_ptr<BasicTile>> tiles[FLOOR_SIZE][FLOOR_SIZE] = {};
+	mutable std::shared_mutex mutex;
 	uint8_t z { 0 };
 };
 
diff --git a/src/map/spectators.hpp b/src/map/spectators.hpp
index 886a51d8c..8e73df9ad 100644
--- a/src/map/spectators.hpp
+++ b/src/map/spectators.hpp
@@ -64,7 +64,7 @@ class Spectators {
 
 	Spectators insert(const std::shared_ptr<Creature> &creature) {
 		if (creature) {
-			creatures.emplace_back(creature);
+			creatures.emplace(creature);
 		}
 		return *this;
 	}
diff --git a/src/pch.hpp b/src/pch.hpp
index ab57f178e..0f5775b73 100644
--- a/src/pch.hpp
+++ b/src/pch.hpp
@@ -32,6 +32,7 @@
 #include <forward_list>
 #include <list>
 #include <map>
+#include <unordered_set>
 #include <queue>
 #include <random>
 #include <ranges>
diff --git a/src/server/network/protocol/protocolgame.cpp b/src/server/network/protocol/protocolgame.cpp
index e81933610..828980b83 100644
--- a/src/server/network/protocol/protocolgame.cpp
+++ b/src/server/network/protocol/protocolgame.cpp
@@ -217,7 +217,7 @@ namespace {
 	 * @param msg The network message to send the category to.
 	 */
 	template <typename T>
-	void sendContainerCategory(NetworkMessage &msg, phmap::flat_hash_set<T> categories = {}, uint8_t categoryType = 0) {
+	void sendContainerCategory(NetworkMessage &msg, const std::vector<T> &categories = {}, uint8_t categoryType = 0) {
 		msg.addByte(categoryType);
 		g_logger().debug("Sendding category type '{}', categories total size '{}'", categoryType, categories.size());
 		msg.addByte(categories.size());
@@ -498,7 +498,12 @@ void ProtocolGame::login(const std::string &name, uint32_t accountId, OperatingS
 
 		if (g_game().getGameState() == GAME_STATE_CLOSED && !player->hasFlag(PlayerFlags_t::CanAlwaysLogin)) {
 			g_game().removePlayerUniqueLogin(player);
-			disconnectClient("Server is currently closed.\nPlease try again later.");
+			auto maintainMessage = g_configManager().getString(MAINTAIN_MODE_MESSAGE);
+			if (!maintainMessage.empty()) {
+				disconnectClient(maintainMessage);
+			} else {
+				disconnectClient("Server is currently closed.\nPlease try again later.");
+			}
 			return;
 		}
 
@@ -2728,7 +2733,7 @@ void ProtocolGame::parseSendBuyCharmRune(NetworkMessage &msg) {
 	g_iobestiary().sendBuyCharmRune(player, runeID, action, raceid);
 }
 
-void ProtocolGame::refreshCyclopediaMonsterTracker(const phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> &trackerSet, bool isBoss) {
+void ProtocolGame::refreshCyclopediaMonsterTracker(const std::unordered_set<std::shared_ptr<MonsterType>> &trackerSet, bool isBoss) {
 	if (!player || oldProtocol) {
 		return;
 	}
@@ -2809,12 +2814,11 @@ void ProtocolGame::BestiarysendCharms() {
 	msg.addByte(4); // Unknown
 
 	auto finishedMonstersSet = g_iobestiary().getBestiaryFinished(player);
-	std::list<charmRune_t> usedRunes = g_iobestiary().getCharmUsedRuneBitAll(player);
-
-	for (charmRune_t charmRune : usedRunes) {
+	for (charmRune_t charmRune : g_iobestiary().getCharmUsedRuneBitAll(player)) {
 		const auto tmpCharm = g_iobestiary().getBestiaryCharm(charmRune);
 		uint16_t tmp_raceid = player->parseRacebyCharm(tmpCharm->id, false, 0);
-		finishedMonstersSet.erase(tmp_raceid);
+
+		std::erase(finishedMonstersSet, tmp_raceid);
 	}
 
 	msg.add<uint16_t>(finishedMonstersSet.size());
@@ -4261,7 +4265,7 @@ void ProtocolGame::sendContainer(uint8_t cid, std::shared_ptr<Container> contain
 	}
 
 	if (container->isStoreInbox()) {
-		auto categories = container->getStoreInboxValidCategories();
+		const auto &categories = container->getStoreInboxValidCategories();
 		const auto enumName = container->getAttribute<std::string>(ItemAttribute_t::STORE_INBOX_CATEGORY);
 		auto category = magic_enum::enum_cast<ContainerCategory_t>(enumName);
 		if (category.has_value()) {
@@ -5819,7 +5823,7 @@ void ProtocolGame::sendPartyCreatureUpdate(std::shared_ptr<Creature> target) {
 
 void ProtocolGame::sendPartyCreatureShield(std::shared_ptr<Creature> target) {
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 		return;
 	}
@@ -5837,7 +5841,7 @@ void ProtocolGame::sendPartyCreatureSkull(std::shared_ptr<Creature> target) {
 	}
 
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 		return;
 	}
@@ -5851,7 +5855,7 @@ void ProtocolGame::sendPartyCreatureSkull(std::shared_ptr<Creature> target) {
 
 void ProtocolGame::sendPartyCreatureHealth(std::shared_ptr<Creature> target, uint8_t healthPercent) {
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 		return;
 	}
@@ -5865,7 +5869,7 @@ void ProtocolGame::sendPartyCreatureHealth(std::shared_ptr<Creature> target, uin
 
 void ProtocolGame::sendPartyPlayerMana(std::shared_ptr<Player> target, uint8_t manaPercent) {
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 	}
 
@@ -5883,7 +5887,7 @@ void ProtocolGame::sendPartyPlayerMana(std::shared_ptr<Player> target, uint8_t m
 
 void ProtocolGame::sendPartyCreatureShowStatus(std::shared_ptr<Creature> target, bool showStatus) {
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 	}
 
@@ -5901,7 +5905,7 @@ void ProtocolGame::sendPartyCreatureShowStatus(std::shared_ptr<Creature> target,
 
 void ProtocolGame::sendPartyPlayerVocation(std::shared_ptr<Player> target) {
 	uint32_t cid = target->getID();
-	if (knownCreatureSet.find(cid) == knownCreatureSet.end()) {
+	if (!knownCreatureSet.contains(cid)) {
 		sendPartyCreatureUpdate(target);
 		return;
 	}
@@ -7808,8 +7812,7 @@ void ProtocolGame::reloadCreature(std::shared_ptr<Creature> creature) {
 
 	NetworkMessage msg;
 
-	phmap::flat_hash_set<uint32_t>::iterator it = std::find(knownCreatureSet.begin(), knownCreatureSet.end(), creature->getID());
-	if (it != knownCreatureSet.end()) {
+	if (knownCreatureSet.contains(creature->getID())) {
 		msg.addByte(0x6B);
 		msg.addPosition(creature->getPosition());
 		msg.addByte(stackpos);
@@ -8308,7 +8311,7 @@ void ProtocolGame::parseBosstiarySlot(NetworkMessage &msg) {
 	addGameTask(&Game::playerBosstiarySlot, player->getID(), slotBossId, selectedBossId);
 }
 
-void ProtocolGame::sendPodiumDetails(NetworkMessage &msg, const phmap::parallel_flat_hash_set<uint16_t> &toSendMonsters, bool isBoss) const {
+void ProtocolGame::sendPodiumDetails(NetworkMessage &msg, const std::vector<uint16_t> &toSendMonsters, bool isBoss) const {
 	auto toSendMonstersSize = static_cast<uint16_t>(toSendMonsters.size());
 	msg.add<uint16_t>(toSendMonstersSize);
 	for (const auto &raceId : toSendMonsters) {
@@ -8388,10 +8391,10 @@ void ProtocolGame::sendMonsterPodiumWindow(std::shared_ptr<Item> podium, const P
 	bool isBossPodium = podium->getID() == ITEM_PODIUM_OF_VIGOUR;
 	msg.addByte(isBossPodium ? 0x01 : 0x00); // Bosstiary or bestiary
 	if (isBossPodium) {
-		const auto unlockedBosses = g_ioBosstiary().getBosstiaryFinished(player, 2);
+		const auto &unlockedBosses = g_ioBosstiary().getBosstiaryFinished(player, 2);
 		sendPodiumDetails(msg, unlockedBosses, true);
 	} else {
-		const auto unlockedMonsters = g_iobestiary().getBestiaryFinished(player);
+		const auto &unlockedMonsters = g_iobestiary().getBestiaryFinished(player);
 		sendPodiumDetails(msg, unlockedMonsters, false);
 	}
 
diff --git a/src/server/network/protocol/protocolgame.hpp b/src/server/network/protocol/protocolgame.hpp
index 2295c1036..8838fc39e 100644
--- a/src/server/network/protocol/protocolgame.hpp
+++ b/src/server/network/protocol/protocolgame.hpp
@@ -145,7 +145,7 @@ class ProtocolGame final : public Protocol {
 	void parseBestiarysendCreatures(NetworkMessage &msg);
 	void BestiarysendCharms();
 	void sendBestiaryEntryChanged(uint16_t raceid);
-	void refreshCyclopediaMonsterTracker(const phmap::parallel_flat_hash_set<std::shared_ptr<MonsterType>> &trackerSet, bool isBoss);
+	void refreshCyclopediaMonsterTracker(const std::unordered_set<std::shared_ptr<MonsterType>> &trackerSet, bool isBoss);
 	void sendTeamFinderList();
 	void sendLeaderTeamFinder(bool reset);
 	void createLeaderTeamFinder(NetworkMessage &msg);
@@ -265,7 +265,7 @@ class ProtocolGame final : public Protocol {
 	void parseSendBosstiary();
 	void parseSendBosstiarySlots();
 	void parseBosstiarySlot(NetworkMessage &msg);
-	void sendPodiumDetails(NetworkMessage &msg, const phmap::parallel_flat_hash_set<uint16_t> &toSendMonsters, bool isBoss) const;
+	void sendPodiumDetails(NetworkMessage &msg, const std::vector<uint16_t> &toSendMonsters, bool isBoss) const;
 	void sendMonsterPodiumWindow(std::shared_ptr<Item> podium, const Position &position, uint16_t itemId, uint8_t stackPos);
 	void parseSetMonsterPodium(NetworkMessage &msg) const;
 	void sendBosstiaryCooldownTimer();
@@ -471,7 +471,7 @@ class ProtocolGame final : public Protocol {
 	friend class Player;
 	friend class PlayerWheel;
 
-	phmap::flat_hash_set<uint32_t> knownCreatureSet;
+	std::unordered_set<uint32_t> knownCreatureSet;
 	std::shared_ptr<Player> player = nullptr;
 
 	uint32_t eventConnect = 0;
diff --git a/src/server/network/protocol/protocolstatus.cpp b/src/server/network/protocol/protocolstatus.cpp
index 315e49a35..778e9c161 100644
--- a/src/server/network/protocol/protocolstatus.cpp
+++ b/src/server/network/protocol/protocolstatus.cpp
@@ -18,7 +18,7 @@
 
 std::string ProtocolStatus::SERVER_NAME = "OTX Server";
 std::string ProtocolStatus::SERVER_VERSION = "6.2";
-std::string ProtocolStatus::SERVER_DEVELOPERS = "Canary Base - OpenTibiaBR Organization and data editor: Mattyx14";
+std::string ProtocolStatus::SERVER_DEVELOPERS = "Canary Base (3.1.1) - OpenTibiaBR Organization and data editor: Mattyx14";
 
 std::map<uint32_t, int64_t> ProtocolStatus::ipConnectMap;
 const uint64_t ProtocolStatus::start = OTSYS_TIME();
diff --git a/src/utils/vectorset.hpp b/src/utils/vectorset.hpp
index 29c6b3766..dab8901bf 100644
--- a/src/utils/vectorset.hpp
+++ b/src/utils/vectorset.hpp
@@ -22,13 +22,13 @@ namespace stdext {
 	public:
 		bool contains(const T &v) {
 			update();
-			return v && std::ranges::binary_search(container, v);
+			return std::ranges::binary_search(container.begin(), container.end(), v, std::less());
 		}
 
 		bool erase(const T &v) {
 			update();
 
-			const auto &it = std::ranges::lower_bound(container, v);
+			const auto it = std::ranges::lower_bound(container.begin(), container.end(), v, std::less());
 			if (it == container.end()) {
 				return false;
 			}
@@ -43,13 +43,13 @@ namespace stdext {
 			return std::erase_if(container, std::move(fnc)) > 0;
 		}
 
-		void push_back(const T &v) {
+		void insert(const T &v) {
 			needUpdate = true;
 			return container.push_back(v);
 		}
 
 		template <class... _Valty>
-		auto emplace_back(_Valty &&... v) {
+		auto emplace(_Valty &&... v) {
 			needUpdate = true;
 			return container.emplace_back(v...);
 		}
@@ -64,6 +64,22 @@ namespace stdext {
 			return container.insert(container.end(), list.begin(), list.end());
 		}
 
+		constexpr auto insert(std::vector<T>::const_iterator _Where, const T &_Val) {
+			needUpdate = true;
+			return container.insert(_Where, _Val);
+		}
+
+		constexpr auto insert(std::vector<T>::const_iterator _Where, T &&_Val) {
+			needUpdate = true;
+			return container.insert(_Where, std::move(_Val));
+		}
+
+		template <std::forward_iterator _Iter>
+		constexpr auto insert(std::vector<T>::const_iterator _Where, _Iter _First, _Iter _Last) {
+			needUpdate = true;
+			return container.insert(_Where, _First, _Last);
+		}
+
 		bool empty() const noexcept {
 			return container.empty();
 		}
@@ -95,6 +111,11 @@ namespace stdext {
 			return container;
 		}
 
+		T &operator[](const size_t i) {
+			update();
+			return container[i];
+		}
+
 	private:
 		void update() noexcept {
 			if (!needUpdate) {
@@ -102,7 +123,7 @@ namespace stdext {
 			}
 
 			needUpdate = false;
-			std::ranges::sort(container);
+			std::ranges::sort(container.begin(), container.end(), std::less());
 			const auto &[f, l] = std::ranges::unique(container);
 			container.erase(f, l);
 		}