Annihilation (5e Creature)
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Colossal unknown, neutral*
Damage Immunities All nonmagical damage
Permanence of Being The nature of this being is such that it is immune to aging, whether magical or otherwise, and when it is reduced to 0 hitpoints it wakes up after 24 hours with full hitpoints. The only way to get rid of Annihilation is to cast Wish on it every day for a year to bind it to a far plane of existence and to a specific deity, which will lose all of it's power until Annihilation returns 100,000 years later. Casting wish on Annhilation for this reason causes the 24 hour countdown to reset.
Undeniable Power This creature ignores invulnerability to damage, and treats resistance as vulnerability.
Purge Melee Weapon Attack: +∞ to hit, reach 30 ft., one target. Hit: 325 (20d12 + 250) Necrotic damage.
Remove Ranged Weapon Attack: +∞ to hit, reach ∞ ft., one target. Hit: 305 (20d12 + 200) Necrotic damage.
Annihilate The DM chooses one plane of existence. Annihilation makes a DC 30 Charisma check. On a fail Annihilation's turn ends and on its next turn it makes the same check, except the DC is reduced by 1. On a success the plane of existence, everything on it, and all deities tied to the plane of existence are destroyed, and cannot be brought back by even the means of a wish spell.
When attacked, the attacker must make a DC 20 charisma save or be teleported to a random area on a random plane of existence.
When the time comes for the multiverse to end, this being knows. When the time comes for it to wake from its endless slumber, this being knows. And it is ready and waiting for the day when the gods power to keep it back fails, and it will destroy every last one of them. There will be a slaughter like none recorded in the history books, and the multiverse will cease to exist. But even then, Annihilation will not stop. For it will create another multiverse and go into a 100,000 year slumber, until the time has come for that multiverse as well to be destroyed.