Shapechanger-Bane Weapon

1st-Level Transmutation

Casting Time: 1 bonus action
Range: Touch
Components: V, S
Duration: Concentration, up to 1 hour

You touch a nonmagical weapon. Until the spell ends, that weapon becomes a magic weapon with a +1 bonus to attack and damage rolls against shapechangers. You can use a bonus action and reduce the duration by 10 minutes to have advantage on attack rolls with the weapon against shapechangers until the start of your next turn.

For the purpose of this spell, “shapechanger” refers to any creature with the Change Shape bonus action or the Shapechanger trait or any creature that isn’t in its true form, such as from the polymorph spell.