Broken

Calm Mind (Flutter Mane) @ Booster Energy / Life Orb 
Ability: Protosynthesis  
Tera Type: Ghost / Fairy / Fire 
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Shadow Ball  
- Moonblast
- Calm Mind  
- Psyshock / Taunt / Mystical Fire
Hex (Flutter Mane) @ Booster Energy / Leftovers
Ability: Protosynthesis  
Tera Type: Ghost  
EVs: 196 HP / 96 SpA / 216 Spe  
Modest Nature  
IVs: 0 Atk  
- Hex  
- Moonblast / Draining Kiss
- Taunt / Calm Mind
- Thunder Wave  
Choice Specs (Flutter Mane) @ Choice Specs
Ability: Protosynthesis  
Tera Type: Ghost / Fairy
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Shadow Ball  
- Moonblast
- Mystical Fire / Hex
- Psyshock

//EDITORS NOTE: Booster Energy is very likely to get the boot early on, but this mon will get hit first
Swords Dance (Chien-Pao) @ Heavy-Duty Boots  
Ability: Sword of Ruin  
Tera Type: Dark  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Icicle Crash / Sacred Sword 
- Sucker Punch / Ice Shard 
- Throat Chop  
- Swords Dance  

Tera Lure (Chien-Pao) @ Life Orb  
Ability: Sword of Ruin  
Tera Type: Electric / Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Icicle Crash  
- Sucker Punch  
- Tera Blast  
- Swords Dance  

Choice Band (Chien-Pao) @ Choice Band  
Ability: Sword of Ruin  
Tera Type: Dark  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Icicle Crash  
- Sacred Sword  
- Throat Chop  
- Ice Shard  

Defensive (Ting-Lu) @ Leftovers  
Ability: Vessel of Ruin  
Tera Type: Ground
EVs: 252 HP / 4 Atk / 252 SpD  
Careful Nature  
- Earthquake  
- Taunt  
- Ruination / Throat Chop / Whirlwind
- Spikes  

Trapper (Ting-Lu) @ Leftovers  
Ability: Vessel of Ruin  
Tera Type: Ground / any
EVs: 252 HP / 4 Atk / 252 SpD  
Careful Nature  
- Sand Tomb  
- Throat Chop  
- Ruination  
- Taunt  

Likely Broken  
Ability: No Ability  

Dragon Dance (Roaring Moon) @ Booster Energy / Chople Berry
Ability: Protosynthesis  
Tera Type: Steel  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant / Jolly Nature  
- Throat Chop  
- Outrage / Earthquake / Scale Shot
- Iron Head  
- Dragon Dance  
Tera Lure (Roaring Moon) @ Booster Energy / Leftovers
Ability: Protosynthesis  
Tera Type: Ground / Flying  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant / Jolly Nature  
- Throat Chop  
- Earthquake / Outrage
- Roost / Tera Blast 
- Dragon Dance  
Choice Specs (Iron Bundle) @ Choice Specs  
Ability: Quark Drive  
Tera Type: Ice  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
- Hydro Pump  
- Freeze-Dry  
- Ice Beam  
- Flip Turn  

Utility Pivot (Iron Bundle) @ Heavy-Duty Boots / Booster Energy
Ability: Quark Drive  
Tera Type: Ice / Water 
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
- Hydro Pump  
- Freeze-Dry  
- Taunt / Encore
- Flip Turn  
Nasty Plot (Chi-Yu) @ Heavy-Duty Boots / Charcoal
Ability: Beads of Ruin  
Tera Type: Dark  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Flamethrower  
- Dark Pulse  
- Overheat  
- Nasty Plot  
Tera Lure (Chi-Yu) @ Heavy-Duty Boots / Life Orb
Ability: Beads of Ruin  
Tera Type: Fighting / Ground / Electric 
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Fire Blast
- Dark Pulse  
- Tera Blast
- Nasty Plot  
Recover Nasty Plot (Gholdengo) @ Leftovers / Colbur Berry / Life Orb
Ability: Good as Gold 
Tera Type: Ghost
EVs: 4 Def / 252 SpA / 252 Spe  
Modest Nature  
IVs: 0 Atk  
- Shadow Ball  
- Make it Rain 
- Nasty Plot  
- Recover  
TrickyPlot (Gholdengo) @ Choice Scarf
Ability: Good as Gold  
Tera Type: Ghost
EVs: 4 Def / 252 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Shadow Ball  
- Make it Rain 
- Nasty Plot  
- Trick

Swords Dance (Iron Valiant) @ Booster Energy / Life Orb
Ability: Quark Drive  
Tera Type: Electric  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Close Combat  
- Spirit Break  
- Thunder Punch  
- Swords Dance 
Ghost Tera (Iron Valiant) @ Booster Energy / Life Orb
Ability: Quark Drive  
Tera Type: Ghost  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Close Combat  
- Tera Blast  
- Shadow Sneak  
- Swords Dance  
Tera Lure (Iron Valiant) @ Booster Energy / Life Orb
Ability: Quark Drive  
Tera Type: Ground  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Close Combat  
- Spirit Break  
- Tera Blast  
- Swords Dance  
Tank (Kingambit) @ Leftovers
Ability: Supreme Overlord
Tera Type: Fairy / Fighting
EVs: 252 HP / 4 Atk / 252 SpD
Careful Nature
- Kowtow Cleave
- Iron Head / Tera Blast / Low Kick
- Sucker Punch
- Swords Dance

Wallbreaker (Kingambit) @ Life Orb
Ability: Supreme Overlord
Tera Type: Dark / Fairy / Fighting
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Kowtow Cleave
- Iron Head / Tera Blast / Low Kick
- Sucker Punch
- Swords Dance

Pure Support (Pawmot) @ Leppa Berry / Focus Sash
Ability: Volt Absorb  
Tera Type: Grass  
EVs: 252 HP / 4 Atk / 252 Spe
Jolly Nature  
- Close Combat
- Ice Punch / Double Shock 
- Nuzzle / Volt Switch / Encore
- Revival Blessing
Offensive Revival (Pawmot) @ Choice Band  
Ability: Volt Absorb  
Tera Type: Grass  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Double Shock
- Close Combat  
- Ice Punch  
- Revival Blessing

//EDITORS NOTE: The broken aspect here is Revival Blessing due to interactions with Leppa Berry. Rabsca can pull off similar shenanigans, but to a much less effective extent.
Shed Tail Abuser (Cyclizar) @ Choice Scarf  
Ability: Regenerator  
EVs: 252 HP / 4 Atk / 252 Spe  
Jolly Nature  
- Shed Tail  
- Knock Off  
- Dragon Tail  
- Ice Spinner

Bulky Shed Tail (Orthworm) @ Leftovers
Ability: Earth Eater
EVs: 252 HP / 4 Def / 252 SpD
Careful Nature
- Iron Head
- Shed Tail
- Rest
- Sleep Talk

//EDITORS NOTE: The aspect likely to get banned here is Shed Tail, not Cyclizar
Solid OU, small risk of being broken  
Offensive SD (Iron Hands) @ Booster Energy
Ability: Quark Drive  
Tera Type: Electric  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Close Combat  
- Wild Charge  
- Ice Punch  
- Swords Dance  

Defensive SD (Iron Hands) @ Booster Energy
Ability: Quark Drive  
Tera Type: Electric  
EVs: 116 Atk / 252 Def / 140 SpD  
Impish Nature  
- Close Combat  
- Wild Charge  
- Ice Punch  
- Swords Dance  

Offensive Spin (Great Tusk) @ Booster Energy / Leftovers
Ability: Protosynthesis  
Tera Type: Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Headlong Rush / Earthquake  
- Close Combat  
- Knock Off  
- Rapid Spin  
Choice Band (Great Tusk) @ Choice Band
Ability: Protosynthesis  
Tera Type: Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Headlong Rush  
- Close Combat  
- Knock Off  
- Ice Spinner

Defensive Spin (Great Tusk) @ Booster Energy / Leftovers
Ability: Protosynthesis 
Tera Type: Ground 
EVs: 252 HP / 252 Def / 4 SpD  
Impish Nature  
- Earthquake  
- Taunt / Stealth Rock
- Knock Off  
- Rapid Spin  
Revenge Killer (Palafin) @ Choice Band
Ability: Zero to Hero
Tera Type: Water / Ground / Ice
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant / Jolly Nature
- Jet Punch
- Flip Turn
- Wave Crash
- Close Combat / Tera Blast / Zen Headbutt

Utility (Palafin) @ Mystic Water / Punching Glove
Ability: Zero to Hero
Tera Type: Water
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant / Jolly Nature
- Jet Punch
- Flip Turn / Close Combat
- Wave Crash
- Taunt
Bulk Up (Palafin) @ Punching Glove / Leftovers
Ability: Zero to Hero
Tera Type: Water
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant / Jolly Nature
- Jet Punch
- Close Combat
- Wave Crash / Zen Headbutt / Taunt
- Bulk Up
Choice Band (Meowscarada) @ Choice Band  
Ability: Protean  
Tera Type: Grass / Dark
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Flower Trick
- Knock Off / Thunder Punch
- U-turn  
- Thunder Punch / Spikes / Sucker Punch / Play Rough

Swords Dance (Baxcalibur) @ Heavy-Duty Boots  
Ability: Thermal Exchange
Tera Type: Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Glaive Rush  
- Icicle Crash / Ice Shard
- Earthquake  
- Swords Dance  

Dragon Dance (Baxcalibur) @ Heavy-Duty Boots  
Ability: Thermal Exchange
Tera Type: Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant / Jolly Nature  
- Glaive Rush  
- Icicle Crash / Ice Shard
- Earthquake  
- Swords Dance  

Choice Band (Baxcalibur) @ Choice Band  
Ability: Thermal Exchange
Tera Type: Ground
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant / Jolly Nature  
- Glaive Rush  
- Icicle Crash  
- Earthquake  
- Ice Shard  

OU Tossup  
Ability: No Ability  
Utility Revenge Killer (Annihilape) @ Choice Scarf
Ability: Defiant
Tera Type: Ghost
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Rage Fist
- Close Combat
- U-turn
- Final Gambit

//EDITORS NOTE: Running 252 HP on this mon will likely be viable - it seems like a very potent Gambit abuser
Defensive (Iron Treads) @ Leftovers / Booster Energy
Ability: Motor Drive  
Tera Type: Ground / any
EVs: 252 HP / 4 Def / 252 SpD  
Careful Nature  
- Earthquake  
- Knock Off  
- Rapid Spin  
- Stealth Rock  
Specially Defensive (Clodsire) @ Leftovers
Ability: Unaware
Tera Type: Ground / Water
EVs: 252 HP / 4 Def / 252 SpD
Careful Nature
- Earthquake
- Toxic
- Recover
- Spikes

Unaware Tank (Skeledirge) @ Heavy-Duty Boots  
Ability: Unaware  
Tera Type: Ghost / Normal
EVs: 252 HP / 252 Def / 4 SpA  
Bold Nature  
IVs: 0 Atk  
- Torch Song 
- Hex  
- Will-O-Wisp  
- Slack Off  

Niche in OU  
Ability: No Ability 
ChestoResto (Dondozo) @ Chesto Berry
Ability: Unaware
Tera Type: Water
EVs: 252 HP / 252 Def / 4 SpD
Impish Nature
- Wave Crash
- Ice Fang / Earthquake
- Curse
- Rest

Offensive (Kilowattrel) @ Heavy-Duty Boots  
Ability: Volt Absorb 
Tera Type: Electric
EVs: 4 Def / 252 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Thunderbolt  
- Hurricane  
- Volt Switch  
- Roost 

Wallbreaker (Maushold) @ Punching Glove / Wide Lens
Ability: Technician
Tera Type: Normal / Dark
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Population Bomb
- Beat Up / Bite
- U-turn / Trailblaze / Thunder Wave
- Tidy Up / Taunt
Hazard Lead (Glimmora) @ Focus Sash  
Ability: Toxic Debris 
Tera Type: Flying
EVs: 252 HP / 4 SpD / 252 Spe  
Jolly Nature  
- Mortal Spin 
- Stealth Rock  
- Memento / Explosion
- Toxic Spikes

Screens Lead (Glimmora) @ Light Clay  
Ability: Toxic Debris 
Tera Type: Flying
EVs: 252 HP / 4 SpD / 252 Spe  
Jolly Nature  
- Mortal Spin / Stealth Rock
- Explosion / Memento
- Reflect  
- Light Screen 

Hail Sweeper (Cetitan) @ Sitrus Berry  
Ability: Slush Rush  
Tera Type: Electric  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Ice Spinner  
- Earthquake  
- Tera Blast  
- Belly Drum  

Setup (Scream Tail) @ Booster Energy
Ability: Protosynthesis 
Tera Type: Psychic  
EVs: 160 HP / 252 SpA / 96 Spe  
Modest Nature  
IVs: 0 Atk  
- Stored Power  
- Dazzling Gleam  
- Calm Mind  
- Bulk Up  

//EDITORS NOTE: I don't expect defensive sets to be viable at all. The defensive typing we're working with here is mediocre and the bulk just isn't high enough
BTEC Blaziken (Quaquaval) @ Life Orb  
Ability: Moxie
Tera Type: Flying  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Aqua Step 
- Close Combat  
- Brave Bird  
- Swords Dance  

Lumina Crash Spammer (Espathra) @ Life Orb
Ability: Speed Boost
Tera Type: Fighting / Psychic
EVs: 252 SpA / 4 SpD / 252 Spe
Timid / Modest Nature
- Lumina Crash
- Dazzling Gleam
- Tera Blast / Shadow Ball 
- Protect / Roost / Calm Mind

Dual Screens (Espathra) @ Light Clay
Ability: Speed Boost
Tera Type: Psychic / any
EVs: 252 HP / 4 SpA / 252 Spe
Timid Nature
- Lumina Crash
- U-turn
- Reflect
- Light Screen

Revenge Killer (Lokix) @ Choice Band  
Ability: Tinted Lens 
Tera Type: Bug / Dark 
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- First Impression  
- Throat Chop  
- U-turn  
- Sucker Punch  

Utility Cleaner (Houndstone) @ Choice Scarf  
Ability: Fluffy  
Tera Type: Ghost  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Last Respects
- Play Rough  
- Trick  
- Will-O-Wisp  

=== Legends Arceus additions below!!! ===
Broken

Extreme Cleaner (Basculegion-M/F) @ Choice Scarf
Ability: Adaptability
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Last Respects
- Wave Crash
- Aqua Jet
- Liquidation
Likely Broken

Specially Defensive (Ursaluna) @ Leftovers / Chesto Berry
Ability: Guts / Bulletproof
EVs: 252 HP / 4 Atk / 252 SpD
Careful Nature
- Double-Edge / Facade
- Headlong Rush / Earthquake
- Fire Punch / Ice Punch / Substitute / Rest / Taunt 
- Swords Dance / Bulk Up
Wallbreaker (Ursaluna) @ Flame Orb
Ability: Guts
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Facade
- Headlong Rush
- Fire Punch / Close Combat
- Swords Dance / Substitute / Ice Punch

//EDITORS NOTE: The following sets assume that Last Respects is banned.
Choice Specs (Basculegion-F) @ Choice Specs
Ability: Adaptability
EVs: 4 Atk / 252 SpA / 252 Spe
Modest / Rash Nature
- Hydro Pump
- Shadow Ball
- Surf / Wave Crash
- Hex

OU Staple
//EDITORS NOTE: The following sets assume that Last Respects is banned.
Choice Band (Basculegion-M) @ Choice Band
Ability: Adaptability
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Wave Crash
- Phantom Force
- Liquidation
- Aqua Jet

Choice Specs (Basculegion-M) @ Choice Specs
Ability: Adaptability
EVs: 4 Atk / 252 SpA / 252 Spe
Modest / Rash Nature
- Hydro Pump
- Shadow Ball
- Surf / Wave Crash
- Hex

OU Tossup
Relentless Spiker (Samurott-Hisui) @ Choice Scarf / Choice Band
Ability: Sharpness
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly / Adamant Nature
- Ceaseless Edge
- Razor Shell
- Knock Off / Aqua Jet
- Sacred Sword
Contrary (Enamorus) @ Heavy-Duty Boots
Ability: Contrary
EVs: 252 Atk / 4 SpA / 252 Spe
Naive Nature
- Play Rough
- Superpower
- Earth Power / Mystical Fire
- Substitute / Taunt / Tailwind

Stone Axe Lead (Kleavor) @ Heavy-Duty Boots / Focus Sash
Ability: Sharpness
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant / Jolly Nature
- Stone Axe
- U-turn / Night Slash
- Close Combat
- Swords Dance
Niche in OU
Choice Band (Sneasler) @ Choice Band
Ability: Poison Touch
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Close Combat
- Gunk Shot
- Shadow Claw / Toxic Spikes
- U-turn

Terrain Sweeper (Sneasler) @ Electric Seed
Ability: Unburden
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Close Combat
- Gunk Shot
- Acrobatics / Shadow Claw
- Swords Dance

Special Attacker (Zoroark-Hisui) @ Heavy-Duty Boots
Ability: Illusion
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Hex
- Will-O-Wisp
- Taunt / Focus Blast
- U-turn / Nasty Plot

Choice Specs (Zoroark-Hisui) @ Choice Specs
Ability: Illusion
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Shadow Ball
- Hyper Voice
- Focus Blast / Flamethrower
- Knock Off / Trick

Victory Dancer (Lilligant-Hisui) @ Life Orb / No Item
Ability: Hustle
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Leaf Blade
- Close Combat
- Ice Spinner / Acrobatics / Sleep Powder
- Victory Dance
Choice Specs (Goodra-Hisui) @ Choice Specs
Ability: Sap Sipper
EVs: 4 Def / 252 SpA / 252 Spe
Modest / Timid Nature
- Draco Meteor
- Flash Cannon
- Fire Blast
- Thunderbolt

Assault Vest (Goodra-Hisui) @ Assault Vest
Ability: Sap Sipper
EVs: 252 HP / 168 SpA / 88 SpD
Sassy / Quiet Nature
- Draco Meteor
- Flash Cannon / Iron Tail
- Flamethrower
- Dragon Tail

Wallbreaker (Arcanine-Hisui) @ Choice Band / Heavy-Duty Boots
Ability: Rock Head
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly / Adamant Nature
- Head Smash
- Flare Blitz
- Wild Charge / Close Combat
- Extreme Speed / Morning Sun / Stealth Rock
Bulky Setup (Enamorus-Therian) @ Heavy-Duty Boots / Kee Berry
Ability: Overcoat
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Draining Kiss
- Earth Power / Mystical Fire
- Calm Mind
- Iron Defense / Moonblast / Springtide Storm