Chatacabra

Camouflage. While the Chatacabra remains motionless, it looks identical to a mound of sand or dirt.

Charge. If the Chatacabra moves at least 15 feet straight toward a target and then hits it with a headbutt attack on the same turn, the target takes an extra 22(4d10) bludgeoning damage

Spit. If the Chatacabra has swallowed a creature, as a bonus action it can spit the creature out, the creature falling prone in a space within 10 feet of the Chatacabra. The creature is then slimed for 1d4 minutes. Whilst slimed, the creature's speed is halved and they have disadvantage on dexterity saving throws and melee attack rolls.

Multi Attack. The x makes two lick attacks, two slam attacks, or one of each.

Lick. The Chatacabra swings it's large tongue covering a 15 foot cone. All creatures within that cone must succeed on a DC 18 dexterity saving throw, taking 16(5d4+4) bludgeoning damage and becoming slimed on a failed save, or half as much on a successful one. When a creature is slimed, for 1d4 minutes the creature's speed is halved and they have disadvantage on dexterity saving throws and melee attack rolls.

Headbutt. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 26(4d10+4) bludgeoning damage. If the creature is medium or smaller, they must also succeed on a DC 14 strength saving throw. On a failed save, they are swallowed. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the Chatacabra.

If the Chatacabra takes 20 damage or more on a single turn from a creature inside it, the Chatacabra must succeed on a DC 19 Constitution saving throw at the end of that turn or spit out the swallowed creature immediately, which fall prone in a space within 10 feet of the Chatacabra. If the Chatacabra dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 15 feet of movement, exiting prone.

whilst a creature has been swallowed, the Chatacabra cannot swallow another creature or use it's lick attack.

Slam. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 29(4d12+4) bludgeoning damage.