I just noticed that all but one examples of acid spray misfires were done by Latch. How random are monster names?
No, all of those sprays hit one of my chars (all the bites too). It's odd that the ai is having such trouble with cones; I've watched the ai toss a Fireball through a narrow doorway and hit two of my chars who were not in the monster's LoS; surely that's much harder to code than a cone.