These expanses of permafrost seem tranquil from a distance, but when a creature approaches, the frozen ground seems to come alive with mouthlike openings that snap at the creature’s feet. The voracious maws are individually small and slow, but their collective bite is debilitating.
Effect: If a creature without ice walk starts and ends its turn in the same ice maws space, it takes 5 cold damage per tier and is immobilized (save ends). The affected creature cannot make a saving throw against this effect until the end of its next turn.
Usage: Large sections of ice maws can encourage characters to pass through an encounter area with haste and discourage ranged attackers from staying in one place. Ice archons are well known for using ice maws to protect their crystalline fortresses.
Published in The Plane Below, page(s) 15.