wazaa

You inscribe a rune of frost on a solid surface within range, which remains dormant until triggered. When a creature moves within 5 feet of the rune, it detonates in a blast of cold energy. The creature must make a Dexterity saving throw. On a failed save, the creature takes 5d8 cold damage, or half as much on a successful one. The rune lasts for up to 10 minutes or until triggered.