When you cast this spell, you place the sharpened metal on the ground and transform it into a frostbound bear trap that occupies a 5-foot square. This trap is nearly invisible, and requires a successful Wisdom (Perception) check to detect it and a successful Dexterity (Sleight of Hand) check to disarm it. The DC for these checks is equal to your spell save DC.   The first time a creature enters the area occupied by this trap, it triggers, it reveals itself, and clamps shut. The creature must make a Dexterity saving throw. If they fail, they take 2d10 piercing damage and 1d10 cold damage, and have their movement speed reduced to 0 while they are trapped.   A creature caught in the trap can be freed by using an action to make a Strength check against your spell save DC. If successful, the creature is freed from the trap. Once a creature is freed from the trap, or the trap is disarmed, the spell ends and the trap vanishes.