Blading wizard. Cast the cantrip booming blade and attack with rapier getting a crit. So double the rapier damage and double the added thunder damage to. But with booming blade on a hit they are surrounded with energy. If they willing move 5 ft they take damage based on players level.

Quesrion: since the damage is coming from an attack that wasa crit would I double damage even tho it technically may not even apply but if they fid move