I built an npc foe for my party to fight using the above combo and it utterly demolished the party tank. My group (and frankly myself) have a feeling that there must be something I've missed bcause it sems way too powerful. I hit the tank twice for 6d6+12 acid twice, the next round they take splash damage from each bomb, 36 total then a round later they take 2d6 extra. Is this right?
As far as I can see there's nothing in the rules that say the sticky effect doesn't stack but this seems a little sily powerwise, is there something I've missed or some errata somewhere, or did I really just drop the party tank with two touch attacks?