Unofficial Tiers
We have so much activity on Pokemon Showdown that I feel comfortable defining "OU" lists for a few other metagames. Treat these as "threat lists" for the various metagames, or use them to play "UU" versions of the metagames by banning these Pokemon.
To refresh your memories,
Little Cup Ubers: Carvanha, Meditite, Gligar, Scyther, Sneasel, Tangela, Vulpix, Yanma
Little Cup OU: Abra, Aipom, Archen, Aron, Axew, Bronzor, Chinchou, Clamperl, Cottonee, Cranidos, Croagunk, Diglett, Dratini, Drifloon, Drilbur, Dwebble, Elekid, Ferroseed, Foongus, Frillish, Gastly, Hippopotas, Houndour, Larvesta, Lileep, Magnemite, Meowth, Mienfoo, Misdreavus, Munchlax, Murkrow, Onix, Pawniard, Ponyta, Porygon, Riolu, Sandshrew, Scraggy, Shellder, Snover, Staryu, Taillow, Tentacool, Timburr, Tirtouga
CAP OU: Abomasnow, Alakazam, Arghonaut, Aurumoth, Breloom, Colossoil, Cyclohm, Dragonite, Ferrothorn, Fidgit, Forretress, Garchomp, Gliscor, Heatran, Jirachi, Keldeo, Kitsunoh, Krilowatt, Latios, Metagross, Mollux, Necturna, Ninetales, Politoed, Pyroak, Revenankh, Rotom-Wash, Salamence, Scizor, Stratagem, Syclant, Tomohawk, Tyranitar, Venusaur, Voodoom
Ubers OU: Arceus, Arceus-Ghost, Arceus-Steel, Blaziken, Blissey, Chansey, Darkrai, Deoxys-Attack, Deoxys-Speed, Dialga, Excadrill, Ferrothorn, Forretress, Garchomp, Genesect, Giratina, Giratina-Origin, Groudon, Ho-Oh, Kabutops, Kyogre, Kyurem-Black, Kyurem-White, Latias, Latios, Lugia, Manaphy, Mewtwo, Palkia, Rayquaza, Reshiram, Shaymin-Sky, Terrakion, Thundurus, Tyranitar, Zekrom