Corrosive Muck

Area all squares in two 10-foot area.

You create two puddles of acidic slime that hinders the movement of anyone who walks through them. The area of each pool becomes greater difficult terrain. Each round that a creature starts its turn in one of the pools or enters a pool during a move action it's using, it takes 8d6 acid damage with a basic Reflex save. A creature that critically fails its saving throw also takes 1d6 acid persistent. As normal, if a Large or larger creature starts its turn in both pools, it takes the damage only once.

Heightened (+2) Create an additional 10-foot burst.