Bullyhug

Slippery. The bullyhug has advantage on checks to avoid being grappled, restrained, or shoved.

Amphibious. The bullyhug can breath air and water

Swallow. The bullyhug  targets one creature it is grappling (does not have to use the Tongue) and swallows it, an unwilling creature must make a DC 12 Strength or Dexterity save (its choice) or be swallowed. While swallowed the creature is considered blinded and restrained, it has total cover from attacks and other effects from outside the bullyhug and regains 1d4 hit points at the start of each of its turns, or, if the creature is at its hit point maximum it instead gains 1d4 temporary hit points. The bullyhug can regurgitate the creature at any time (no action required) and it automatically regurgitates the creature if it dies.

Tongue Slam. Melee Weapon Attack: +4 to hit, reach 10 ft., # target. Hit: 4 (1d4 + 2) Acid damage. If the creature is tiny, it is pulled within 5 feet of the bullyhug and grappled.