You can use an action to blow this horn. Any demons who hear this horn blown must make a DC 15 Charisma saving throw or be banished, as the banishment spell, returning to their plane of origin. If this is blown on the demon’s native plane, demons within 60 ft. take 21 (6d6) points of thunder damage instead.

Once this horn is used, it cannot be used again for 3d4 days. These hunting horns are usually made of an unusual material such as amber or ebony.

Notes: Castle Amber Conversion Guide and Expansion Original Adventure by Tom Moldvay Conversion to 5e and Expansion Notes by Stuart Broz