You launch a shard of temporal magic at a creature within range, forcing it to make a dexterity saving throw. On a failed save, the creature takes 3d8 force damage and is temporally anchored for the duration.   When the anchored creature takes an action, you can end your concentration on this spell (no action required), activating the anchor and negating the action. When the spell ends, the anchored creature can't take an action until the beginning of its next turn.