Cajón

Thunder Absorption. Whenever Cajon is subjected to thunder damage, it takes no damage and instead regains a number of hit points equal to the thunder damage dealt.

Fiendish Privilege. If Cajon dies outside the Lower Planes, it comes back to life in the Abyss with all its hit points in 1d10 days unless it is killed by a good-aligned creature with a bless spell cast on that creature or its remains are sprinkled with holy water.

 Axe. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 9 (1d12 + 3) slashing damage.

Drum Beat (Recharge 6). Cajon creates a 15-foot cube originating from it. Each creature in that area must make a DC 13 Constitution saving throw, taking 9 (2d8) Thunder damage on a failed save and is pushed 10 ft. away from Cajor, or half as much damage on a successful one and is not pushed. In addition, unsecured Objects that are completely within the area of Effect are automatically pushed 10 feet away from you by the Effect, and the Effect emits a thunderous boom audible out to 300 feet.

Horrifying Visage (1/Day). Each non-undead creature within 60 feet of Cajon that can see him must succeed on a DC 13 Wisdom saving throw or be frightened for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, with disadvantage if the banshee is within line of sight, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to Cajon's Horrifying Visage for the next 24 hours.