Other Version s/o to KyogreF4N

Marshadow @ Life Orb
Ability: Technician
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Shadow Sneak
- Spectral Thief
- Close Combat
- Substitute

Rayquaza-Mega @ Choice Scarf
Ability: Delta Stream
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Dragon Ascent
- V-create
- Outrage
- Earthquake

Arceus-Poison @ Poisonium Z
Ability: Multitype
EVs: 8 HP / 248 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Recover
- Calm Mind
- Sludge Bomb
- Fire Blast

Arceus @ Leftovers
Ability: Multitype
EVs: 216 HP / 252 Atk / 40 Spe
Adamant Nature
- Substitute
- Swords Dance
- Extreme Speed
- Shadow Claw

Arceus-Fairy @ Pixie Plate
Ability: Multitype
EVs: 252 HP / 176 Def / 16 SpA / 56 SpD / 8 Spe
Bold Nature
IVs: 0 Atk
- Recover
- Toxic
- Stealth Rock
- Judgment

Arceus-Ground @ Earth Plate
Ability: Multitype
EVs: 252 HP / 56 Def / 96 SpA / 104 Spe
Timid Nature
IVs: 0 Atk
- Recover
- Defog
- Ice Beam
- Judgment