Trekker's Terrible Terrain

Upon striking the ground, cold frost creeps swiftly to a desired point. The ground or a wall in a 20-foot radius centered on a desired point within 60 feet of you grows large sharp icicles. The area becomes difficult terrain for the duration. A creature caught in the area when cast or a creature that moves into or within the area takes 1d4 cold piercing damage for every 5 feet it travels. The terrain is obviously ice spikes and can be easily seen. After 1 minute, the terrain shatters. Any creature within the area during this time takes an additional 3d4 cold damage.