Standing next to a hezrou may induce nausea

[copperwater]

This could repurpose the defunct abattoir sickness code to instead scan the area around the hero for a hezrou. It should happen at fairly low frequency (so that you're not guaranteed to get nauseous just from being near a hezrou for a few turns).

This should happen only if olfaction() is true.

A different but more complicated implementation would be to make the gas clouds emitted by hezrous, and only those gas clouds, induce nausea.