Divine Assassin

 You invoke the spirit of a long-dead assassin to follow your commands. The assassin is invisible, but to creatures with Truesight or See Invisibility, it appears as a faint outline of a person, glowing in either yellow or green light, depending on the damage type you choose (radiant or necrotic).

Upon casting the spell, the assassin dashes toward a target you choose within range, stalking its prey intangibly. At the end of the target's second turn after the spell is cast, the assassin strikes, dealing 3d12 damage of the chosen type (radiant or necrotic). After the attack, the assassin vanishes back into the ether.

This spell can be cast even if you have already used a leveled spell this turn.