Elemental Bane

4th-Level Transmutation

Casting Time: 1 action
Range: 90 feet
Components: V, S
Duration: Concentration, up to 1 minute. 

Choose one creature you can see within range, and choose one of the following damage types: acid, cold, fire, lightning, or thunder. The target must succeed on a Constitution saving throw or be affected by the spell for its duration. While under the effects of this spell, the target gains vulnerability to the chosen damage type until the spell ends. If the target has resistance to the damage type, it loses the damage resistance. If the target has immunity to the damage type, it loses its vulnerability and gains only resistance to the damage type. 

If the target drops to 0 hit points before this spell ends, you can use a bonus action on your turn to force a new target creature to make a Constitution saving throw. The target must fail the saving throw in order to be affected by the same spell. If the target succeeds, the spell ends.

Spell Lists: Artificer, Druid, Warlock, Wizard, College of Lore Bard