>>31341784Umbreon is great if you teach it Toxic, Protect, Confuse Ray and Moonlight. It walls almost everything.
But anyway, here is the "competitive" team everyone uses in Colosseum:
Espeon
Typlosion
Quagsire
Ampharos
Misdreavus
Hitmontop
During the playthrough, most people replace Typlosion with Entei, Quagsire with Suicune, Ampharos for Raikou and Misdreavus with Forretress. People also like to throw in Flygon, simply because it's a strong Earthquake user.
Misdreavus is really good early on, because the early AI can't handle ghost types and will try to attack it with normal moves the entire time. They get smarter though and it loses out on stats later on, so don't feel bad for dumping it.
Other Options include Hariyama and Meditite (Fighting types with Fake Out), Granbull (Intimidate), Feraligator (if you don't want to use the other two excellent water types) and Altaria for being a Dragon.
Even though you get them very late, Heracross and Skarmory are top tier pokemon, so many players go out of their ways to purify them just for the final fight.