ToME Wiki[2.2.7]
sometimes with many pets they don't give way, although they could expand somewhere. this seems related to obstacles; in really free areas it doesnt seem to happen.
When this problem appears you get "Your Foobar is in the way!" and you actually HIT him (at least the enemy health bar says so!)
this can lead to massive lossage when you're jailed by pets, or escape them just to stumble into a nest of Qs.
SimonSorc: This occurs a lot when you can treewalk and your pets can, or you can fly over things but your pets can. However hitting the pet I couldn't duplicate in [2.3.0]
NeilStevens: Pets don't "give way" or "expand." They switch places with you. So, if you're flying over a tree and step into a non-flying pet, or are climbing and step into any pet (no monsters have climbing), or are using wraith form and are in a wall and step into a pet that can't pass through walls, it won't work.
If you try to step into a pet you can't see, or are confused, walking into one will attempt to attack that monsters.
So, I'm not sure what the bug is.
VagaBond: I had a character with two companions, both of those were able to go through junks and forest. (Pit fiend and Great Wyrm of Power) I wasn't able to change places with them when I was flying over a pile of junk or trees.. So something is really bugging here yet.
ReenenLaurie: AFAIK you cannot switch places with monsters while you are on a square where the monster needs flying, even if the monster does in fact have flying. This is easy enough to test (but I don't have ToME here), and then it should be a bug.
k [Original bugreporter]: Yes, you're right. So it just LOOKS as if they "give way", and cannot if in wall. I stumbled into this problem while playing LostSoul; if you find a herd of co-aligned High-elven rangers you're in for a party, subsequent morph, summon etc. gave a herd of about 100 various formidable pets. No flying or trees, I think the problem was that I accidentally went into a piece of freestanding wall (or came out of the wall, in wraith form). So, this is strictly not a bug (unless someone can confirm the hitpoint loss in pets), but can be very annoying to WraithForms. Is there a pet command for "give a little room"? <P> seem to have "come here!" and "seek out and destroy", but I didn't notice much difference.