Legendary Resistance (2/Day). If the balhannoth fails a saving throw, it can choose to succeed instead.
Multiattack. The balhannoth makes one Bite attack and two Tentacle attacks.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit:19 (3d10 + 3) piercing damage.
Tentacle. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit:10 (2d6 + 3) bludgeoning damage, and the target is grappled (escape DC 15) and is moved up to 5 feet toward the balhannoth. Until this grapple ends, the target is restrained, and the balhannoth can't use this tentacle against other targets. The balhannoth has four tentacles.
Bite. The balhannoth makes one Bite attack against one creature it has grappled.
Teleport. The balhannoth teleports, along with any equipment it is wearing or carrying and any creatures it has grappled, up to 60 feet to an unoccupied space it can see.
Vanish. The balhannoth magically becomes invisible for up to 10 minutes or until immediately after it makes an attack roll.
Native to the Shadowfell, the vicious, predatory balhannoth alters reality in its lair to make the place appear inviting to travelers. A limited form of telepathy enables a balhannoth to identify images of places where its prey expects their needs and desires to be met, such as an inn or a temple offering healing. It then warps reality around itself, hiding itself and remaking its environment to resemble such a place. The imitation is imperfect, but it's good enough to fool greedy or desperate…