Here it is:
Xerneas@Power Herb
Ability: Fairy Aura
EVs: 252 Sp Atk / 4 Sp Def / 252 Spe
Bold Nature
Geomancy
Moonblast
Psychic/Psyshock
Focus Blast/Calm Mind
This isn't the best. I'm still debating whether to switch out Calm Mind or not. Here's how this thing works(BTW I have Psyshock, not Psychic): Geomancy to set up. Moonblast wrecks everthing. Psyshock is to kill Poison types. Focus Blast kills Steel but usually after I sweep a pokemon I go Calm Mind, making it tougher for Special Sweepers.
Rayquaza@Life Orb
Ability: Air Lock--->Delta Stream
EVs: 4 HP / 252 Sp Atk / 252 Spe
Modest Nature
Dragon Ascent
Flamethrower
Dragon Pulse
Ice Beam
I designed this myself. After that Dragon Ascent also mega evolves it after using it always. Flamethrower wrecks ice and Dragon Pulse beats , well, Dragon. Ice Beam covers a lot of types.
Venusaur@Black Sludge
Ability: Overgrow
EVs: 252 HP / 4 Sp Atk / 252 Sp Def
Calm Nature
Leech Seed
Synthesis
Giga Drain
Sludge Bomb
Man, this thing annoys everybody. Leech Seed saps them and Giga Drain+Black Sludge and synthesis = constant health. I survived a flamethrower kommo-o and just eventually sapped it.
Politoed@Damp Rock
Ability": Drizzle
EVs: 252 HP / 4 Sp Atk / 252 Sp Def
Timid Nature
Scald
Ice Beam
Focus Blast
Psychic
Ice Beam ruins Grass type+freezing. Psychic is special, Scald is STAB, Focus Blast just for the heck of it. This thing comes in after Cloyster has spiked everything. Red Card drags everything out. I hope you see the downsides. After this comes Volcarona...
Volcarona@Red Card
Ability: Swarm
EVs: 252 Sp Atk / 4 Sp Def / 252 Spe
Bold Nature
Quiver Dance
Bug Buzz
Fiery Dance
Giga Drain
Do I need to explain?
Cloyster@Focus Sash
Ability: Skill Link
EVs: 252 HP / 252 Def / 4 Sp Def
Impish Nature
Spike Cannon/Rock Blast
Spikes
Toxic Spikes
Icicile Spear
This thing is abusing Skill Link. Spiker, yah! Spikes once and toxic spikes. I like to get on two layers of toxic spikes, tho. I spam spikes and Spikes Cannon has better accuracy but Rock Blast has more damage and can beat Ice, Flying, and Ground/Fighting. I spikes 'em and toxic too, then Icicle Spear. If it's PP runs out S[ikes Cannon/Rock Blast, assuming it lives that long. And Volcarona pours sand into their wounds by dragging each one of them out onto the spikes. EPIC.