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?
I'm not sure I understand the question here, but if I am interpreting your last statement correctly you seem to be asking about outsiders chain summoning other outsiders? That doesn't work RAW as summoned creatures don't have access to their teleportation, summon, and costly material component effects; if a dretch summoned another dretch, that new dretch would not have access to the summon ability. If that's not what you meant then could you clarify?
I'm not sure I understand the question here, but if I am interpreting your last statement correctly you seem to be asking about outsiders chain summoning other outsiders? That doesn't work RAW as summoned creatures don't have access to their teleportation, summon, and costly material component effects; if a dretch summoned another dretch, that new dretch would not have access to the summon ability. If that's not what you meant then could you clarify?
Yes, this was my main issue, but if the new demon can't summon any other demons all will be good, thanks.