Aspect of Arceus

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

Magical Attacks. Arceus' attacks are considered to magical for the purpose of overcoming resistances and immunities.

Godly Invincibility. As Arceus is a god, he cannot be truly killed. If he is reduced to 0 Hit Points, he returns to The Hall of Origin to rest.

Multitype. When Arceus starts his turn, he can choose a single damage type to gain an immunity to. This lasts until the start of his next turn.

Legend Plate. When Arceus starts his turn, he can choose a damage type to apply to his Judgement attack, doing that damage type instead of radiant with an added affect from the list below, however, this means that the target(s) are not blinded:
Bludgeoning. If Bludgeoning is selected, it does the normal amount of damage, but, in addition, the target(s) must succeed a DC 22 Strength saving throw or fall prone.
Slashing. If Slashing is selected it does the normal amount of damage, but, in addition, the target(s) must succeed a DC 22 Strength saving throw or drop any weapon they are currently holding.
Piercing. If Piercing is selected it does the normal amount of damage, but, in addition, the target(s) AC is reduced by 2 until the start of their next turn.
Acid. If Acid is selected it does the normal amount of damage, but, in addition, the target(s) movement speed is decreased by 10ft. until the start of Arceus' next turn.
Cold. If Cold is is selected it does the normal amount of damage, but, in addition, the target(s) have disadvantage on their next attack roll.
Fire. If Fire is selected it does the normal amount of damage, but, in addition, the target(s) take 2d6 fire damage at the start of their turn for 2 rounds.
Force. If Force is selected, Judgement does an additional 6d6 force damage.
Lightning. If Lightning is selected it does the normal amount of damage, but, in addition, the target(s) cannot take reactions for 1 round.
Necrotic. If Necrotic is selected it does the normal amount of damage, but, in addition, the target(s) must succeed a DC 22 Constitution saving throw or have their maximum hit points reduced by the amount of damage taken.
Poison. If Poison is selected it does the normal amount of damage, but, in addition, the target(s) must succeed a DC 22 Constitution saving throw or be poisoned for 1 minute.
Psychic. If Psychic is selected it does the normal amount of damage, but, in addition, the target(s) have to subtract ad6 from their next attack roll or saving throw.
Thunder. If Thunder is selected it does the normal amount of damage, but, in addition, the target(s) are deafened and pushed backwards 10ft.

Almighty Sinnoh. Arceus cannot have his ability scores modified, have his shape changed, or have his maximum hit point count reduced against his will.

Alpha Pokémon. Arceus has +5 to initiative rolls.

Draco Meteor (Recharge 6). Arceus roars and a glowing draconic meteor plummets from the sky to a single spot Arceus can see, causing it to explode in a 15ft. radius. Any creature in range must succeed a DC 26 Dexterity saving throw or take 20d6 force damage plus 10d6 radiant damage.

Hyper Voice. Arceus releases a shockwave that crackles with energy in a 50ft. radius. Any creature in range must succeed a DC 25 Dexterity saving throw or take 14d6 force damage plus 6d6 radiant damage or half as much on a success.

Arceus can take 4 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Arceus regains spent legendary actions at the start of its turn.

Judgement (Costs 4 Actions). Arceus raises itself onto his hind legs as a glowing orange ball of his own energy appears above him. A set of beam shoot out of it at a single point that Arceus can see. The beams explode in a 25ft. radius. Any creature in range must succeed a DC 25 Dexterity saving throw or take 26d6 radiant damage and be blinded for 2 rounds.

Spatial Rend (Costs 4 Actions). Arceus starts glowing with blue light, as balls of energy gather around him as the space around him becomes distorted. Arceus then releases this energy in a 50ft. radius. Any creature within range must succeed a DC 25 Dexterity saving throw or take 26d6 force damage and be pushed 20ft. away from Arceus as the space around them shatters like a broken window. On a success, they take half damage.

Roar of Time (Costs 4 Actions). Arceus opens his mouth and a beam of time energy is released in a 5ft. wide, 90ft. long beam. Any creature in range must succeed a DC 26 Dexterity saving throw or take 10d6 force damage and be paralyzed for one minute. A paralyzed creature can repeat the save at the start of their turn as a DC 26 Wisdom saving throw.

Shadow Force (Costs 4 Actions). Arceus teleports to a spot he can see within 90ft. and makes an explosion of shadowy energy in a 20ft. radius. Any creature in range must succeed a DC 25 Dexterity saving throw or take 20d6 force damage or half as much on a success.

Teleport (Costs 2 Actions). Arceus teleports to a spot he can see within 150ft.

Move. Arceus moves up to his full movement speed.