A lot of demons have the summon monster spell like ability with some kind of percentage, so how do you use this in combat?
I'm thinking more on the lines of "dm rolling" it, here's a particular case but it can apply to a lot of other encounters:
I have a 2 dretch encounter, each one has a 35% of summoning another dretch, I believe that 2 is too little with 3 being appropiate, so I'm planning on just summoning an addtional dretch, before the first dretch dies.
I'm curious on how everyone else plays with this, do you just make the roll and let as many demons as they can summon come?