Multicolor Pokmon do exist, but a lack of energy fixing makes them a lot harder to play without putting some serious work into it
I should note that those arent distinct groups
Carmen does cost five, though, so the rest of your deck should be filled with equal amounts of recursion (Sevinnes Reclamation et al), ramp (Ancient Tomb, Sword of the Animist) and evasive bodies that can also grow tall (Voldaren Bloodcaster, Liberator, Urzas Battlethopter, Serra Ascendant)
With just one unblocked hit because of its trample and infect and power of 11, an opponent can instantly lose the game
The -3/-3 from Locthwain Scorn is enough to take down most of the one, two, and three mana creatures in the format