Chry, Titan of World's End

Legendary Resistance (3/day). If Chry should fail a saving throw, it may instead choose to succeed.

Siege Monster: Chry deals double damage to walls and structures.

Spellcasting. Chry is a 20th level spellcaster. Its spellcasting ability is WIS (spell save DC 20, +10 to hit with spell attacks). Chry has following spells prepared:
1st Level (10 slots): [Chaos Bolt], [Earth Tremor], [Hellish Rebuke]
2nd level (10 slots): [Shatter]

3rd level (6 slots): [Fireball], [Pulse Wave]

9th level (2 slots): [Meteor Swarm], [Ravenous Void]

Multi Attack:  Chry makes 3 attacks. 2 with its tendrils and 1 with its tusks

Tendrils. Melee Weapon Attack: +10 to hit, reach 30 ft., 1 target. Hit: 6d6 + 10) necrotic damage. 

Tusks. Melee Weapon Attack: +10 to hit, reach 10 ft., 1 target. Hit: 4d8 + 10) necrotic damage. 

Chry may make 5 legendary actions, but only 1 per turn. 1 action is restored at the end of its turn.

Unmake (Costs 2 Actions). Chry unleashes primordial power against a creature. The target must make a DC20 CON save or become ravaged by wild power, reducing 1 from every stat and aging the character by 10 years.

Tempest (Costs 3 Actions). Chry summons a maelstrom of untamed magic. For 1 minute, the storm swirls overhead and around the battlefield. The entire battlefield is overcome with violent gales. Any creature attempting to move must succeed a DC16 STR check to be able to move fully. A failed check reduces the move by 20 feet. The storm also lashes out, throwing bolts of lightning about the battlefield. 1d4 random creatures must make a DC18 DEX save or become the target for the lightning bolt spell.

Reality Bomb. Chry rears up, exposing its underside, revealing a roiling vortex of primordial creation energy. This energy coalesces and begins to pull everything around it into its hungry black maw and lasts  3 rounds. Everything within 100 ft of Chry must take a DC18 STR check or be pulled a distance equal to 10x the number the check was failed by ft towards the vortex. Creatures within 50 feet of Chry take damage as the vortex energy begins to unravel their very being, taking 1d10 damage for every 10 feet closer the creature gets. Should a creature fail their saving throw within 10 ft of the vortex, they are sucked in and annihilated, unravelled molecule by molecule.