Bebilith

Demonic Restoration. If the bebilith dies outside the Abyss, its body dissolves into ichor, and it gains a new body instantly, reviving with all its Hit Points somewhere in the Abyss.

Spider Climb. The bebilith can climb difficult surfaces, including along ceilings, without needing to make an ability check.

Web Walker. The bebilith ignores movement restrictions caused by webs, and it knows the location of any other creature in contact with the same web.

Multiattack. The bebilith makes one Bite attack and one Rend attack. It can replace one attack with a use of Web if available.

Bite. Melee Attack Roll: +13, reach 10 ft. Hit: 19 (3d6 + 9) Piercing damage plus 7 (2d6) Poison damage, and the target is Poisoned until the end of the bebilith's next turn.

Rend. Melee Attack Roll: +13, reach 10 ft. Hit: 19 (3d4 + 9) Slashing damage. Nonmagical armor worn by the target takes a −1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10. The penalty can be removed by casting the Mending spell on the armor.

Web (4/Day). Constitution Saving Throw: DC 13, one creature the bebilith can see within 30 feet. Failure: The target has the Restrained condition (escape DC 21) until the web is escaped or destroyed (AC 10; HP 14; Immunity to Poison and Psychic damage).

Plane Shift (1/Day). The bebilith casts Plane Shift on itself only, without spellcasting components and using Charisma as the spellcasting ability (spell save DC 13).