@ Pizu:
I don't recall having made a script for such old levels where something like that happens.
In fact, I don't believe it is even possible to make creatures switch allegiance on the spot.
If it was a snow level, then chances are they were simple adds that happened to pop by. If you're talking about the level that I -think- you're talking about, there were a lot of creature parties in that one.
In any case it's impossible they suddenly switched allegiance.
@ Topic:
Probably something Bullfrog never got to implement, like so many things and mistakes. Horny going crazy is a joke, keeping dragons calm is easy.