Player-4
See you in 25 years
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Standard Rules:
Sleep clause:
You can't use sleep inducing moves on an opponent's Pokémon when there's another Pokémon on his/her team asleep. Yawn can't be used to PseudoHaze (make opponent switch) when there's another Pokémon asleep caused by you. When the asleep Pokémon awakens or faints, you're free to make another Pokémon of his/her team asleep. Sleep caused by Effect Spore or Rest are excluded from Sleep Clause.
Species clause:
You can't use two of the same Pokémon in a team. I.E. 2 Scizors.
Evasion clause:
You can't use moves that increases your evasion. I.E. Double Team and Minimize.
Self-KO clause:
This clause covers two things. First, when you and your opponent have only one Pokémon left, if you use Explosion or Self-Destruct, you automatically lose. Also, if you use Destiny Bond, with your last Pokémon, and your opponents last Pokémon faints you, you still lose. This clause was made to stop matches from ending in a tie. Recoil moves (Brave Bird, Double-edge, etc.), however, are excluded from this rule.
OHKO clause:
You are strictly prohibited of using OHKO moves. They are Guillotine, Horn Drill, Fissure and Sheer Cold.
No Hacks:
You cannot use Pokemon with illegal moves or stats (999 in all stats or something ridiculous). Legal Pokesav is fine.
No Hax Items*:
These are all the items that rely on luck to activate: Brightpowder, Focus Band, King's Rock, Lax Incense, Quick Claw, Razor Fang, Razor Claw, Scope Lens, Lansat Berry, Stick, and Lucky Punch.
Uber Tier
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The following are banned from OU/BL/UU/NU
Arceus
Darkrai
Deoxys (all forms)
Dialga
Garchomp
Giratina
Giratina-O
Groudon
Ho-oh
Kyogre
Latias
Latios
Lugia
Manaphy
Mew
Mewtwo
Palkia
Rayquaza
Shaymin-S
Wobbuffet
Wynaut
Over Used (OU) Tier
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The following are banned from BL/UU/NU:
Aerodactyl
Azelf
Blissey
Breloom
Bronzong
Celebi
Dragonite
Dusknoir
Electivire
Empoleon
Flygon
Forretress
Gengar
Gliscor
Gyarados
Heatran
Heracross
Hippowdon
Infernape
Jirachi
Jolteon
Kingdra
Lucario
Machamp
Magnezone
Mamoswine
Metagross
Ninjask
Rotom-forms
Salamence
Scizor
Skarmory
Smeargle
Snorlax
Starmie
Suicune
Swampert
Tentacruel
Togekiss
Tyranitar
Umbreon
Vaporeon
Weavile
Zapdos
Border Line (BL) Tier
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The following are banned from UU/NU:
Abomasnow
Cresselia
Crobat
Froslass
Gallade
Honchkrow
Porygon-Z
Raikou
Shaymin
Staraptor
Yanmega
Under Used (UU) Tier
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The following are banned from NU:
Absol
Aggron
Alakazam
Altaria
Ambipom
Arcanine
Azumarill
Blastoise
Blaziken
Chansey
Claydol
Clefable
Cloyster
Donphan
Drapion
Drifblim
Dugtrio
Feraligatr
Hariyama
Hitmonlee
Hitmontop
Houndoom
Kabutops
Lanturn
Leafeon
Ludicolo
Mesprit
Milotic
Mismagius
Moltres
Nidoking
Nidoqueen
Omastar
Poliwrath
Qwilfish
Regirock
Registeel
Rhyperior
Rotom
Sceptile
Scyther
Slowbro
Spiritomb
Steelix
Swellow
Tangrowth
Torterra
Toxicroak
Typhlosion
Uxie
Venusaur
Weezing
Never Used (NU) Tier
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Ampharos
Arbok
Ariados
Armaldo
Articuno
Banette
Bastiodon
Beautifly
Beedrill
Bellossom
Bibarel
Butterfree
Cacturne
Camerupt
Carnivine
Castform
Charizard
Chatot
Cherrim
Chimecho
Clamperl
Corsola
Cradily
Crawdaunt
Delcatty
Delibird
Dewgong
Ditto
Dodrio
Dunsparce
Dustox
Electrode
Entei
Espeon
Exeggutor
Exploud
Farfetch'd
Fearow
Flareon
Floatzel
Furret
Gardevoir
Gastrodon
Girafarig
Glaceon
Glalie
Golduck
Golem
Gorebyss
Granbull
Grumpig
Hitmonchan
Huntail
Hypno
Illumise
Jumpluff
Jynx
Kangaskhan
Kecleon
Kingler
Kricketune
Lapras
Ledian
Lickilicky
Linoone
Lopunny
Lumineon
Lunatone
Luvdisc
Luxray
Magcargo
Magmortar
Magneton
Manectric
Mantine
Marowak
Masquerain
Mawile
Medicham
Meganium
Mightyena
Miltank
Minun
Mothim
Mr. Mime
Muk
Ninetales
Noctowl
Octillery
Pachirisu
Parasect
Pelipper
Persian
Phione
Pidgeot
Pikachu
Pinsir
Plusle
Politoed
Porygon2
Primeape
Probopass
Purugly
Quagsire
Raichu
Rampardos
Rapidash
Raticate
Regice
Regigigas
Relicanth
Sableye
Sandslash
Seaking
Seviper
Sharpedo
Shedinja
Shiftry
Shuckle
Skuntank
Slaking
Slowking
Solrock
Spinda
Stantler
Sudowoodo
Sunflora
Swalot
Tauros
Torkoal
Trapinch
Tropius
Typhlosion
Unown
Ursaring
Venomoth
Vespiquen
Victreebel
Vigoroth
Vileplume
Volbeat
Wailord
Walrein
Whiscash
Wigglytuff
Wormadam
Wormadam-G
Wormadam-S
Xatu
Zangoose
*Hax items are not actually banned in standard rules, though they are frowned upon. However, if you do not want your opponent using hax items, just ask for a "Standard (insert tier here), no hax items" and you're set to go!
If I missed anything please let me know!