Cho'Gath

Legendary Resistance (3/day): If Cho' Gath fails a saving throw, he can choose to succeed instead. 

Carnivore. Anytime that Cho'gath kills and eats a creature that is flesh and blood, he regains half of that creature's hit dice back as health. Cho'Gath's bite attacks automatically hit and swallow unconscious or dead creatures.

Evolution: Vorpal Spikes. When Cho'Gath is at half health or less, his claw attacks now shoot a wall of spikes past his target. When Cho'Gath hits with a claw attack, all creatures behind the target in a 30 ft line must make a DC 20 Dexterity save or take 24 (3d8+10) piercing damage. 

Siege Monster: Cho' Gath deals double damage to objects and structures.

Multiattack. Cho'gath makes three claw attacks, or two claw attacks and one bite. If Cho'Gath currently has a creature in his mouth,  the bite attack can be replaced with a swallow attack.

Claw. Melee Weapon Attack: +12 to hit, reach 20 ft., 1 target. Hit: 28 (4d8+10) slashing damage. 

Bite. Melee Weapon Attack: +12 to hit, reach 20 ft., 1 target. Hit: 36 (4d12+10) piercing damage and the target is grappled. 

Swallow. Cho'Gath makes one bite attack against a creature he is grappling. If the attack hits, the target takes the bite’s damage, the target is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside Cho' Gath, and it takes 56 (16d6) acid damage at the start of each of Cho' Gath's turns.

If Cho' Gath takes 60 damage or more on a single turn from a creature inside him, Cho' Gath must succeed on a DC 20 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the tCho' Gath. If Cho' Gath dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 30 feet of movement, exiting prone.

If Cho'Gath kills a creature by digesting it, the Carnivore trait kicks in and Cho'Gath gains half of the creature's hit dice back as health. 

Cho' Gath is a legendary creature that has legendary actions. These legendary actions can only be taken at the end of another creature's turn. Cho'Gath gets all used legendary actions back at the start of his next turn. 

Rupture (Costs 1 Action). Cho'Gath stomps the ground, causing a ring of spikes to shoot up from a rift in the void and launching his enemies into the air. Choose a point within range. All creatures except Cho'Gath within 60 feet of that point must make a DC 20 Dex or Strength saving throw or be launched 20 feet into the air, taking 24 (3d8+10) piercing damage not including fall damage and land prone. Those who succeed their save take half damage and are not tossed into the air. 

Feral Scream (Costs 1 Action). Cho'Gath screams a primal scream in a 100 foot long, 50 foot wide cone. All creatures in this cone must make a DC 20 Constitution Saving throw or take 24 (3d8+10) thunder damage and be silenced until Cho'Gath's next turn. Those who succeed their save take half damage and are not silenced. 

Attack (Costs 2 Actions). Cho'Gath makes one claw and one bite attack. If Cho' Gath is already grappling a creature through Bite, the bite attack may be replaced with a Swallow attack.