While playtesting in The Gulag's Solitary Confinement - Wing A, I spawned extra mobs by killing the nesting monsters (as designed). Two of the mobs that were spawned, however, were stuck in a stalagmite. I was able to kill them, but with no risk to myself.

I had a mob, a poison puker that was stuck behind a shrine this morning. I couldn't get close to the shrine without taking psn dmg. Finally I had to fire bolt the thing hoping I didn't destroy the shrine.