pokemon cards slowpoke - ME05: Pitch Black variation to centering Pokemon Card Game/[SV2a] Pokemon Card

That can be done to help whoevers behind, to break key synergies, make players exchange commanders, and so on

Blue has plenty of other illusions like Phantasmal Image to help buff Minns tokens

Overmaster is the best, followed by some haste enablers, then a bunch of effects that you might not care about other than the draw effect ( glances significantly over at Warlord's Fury )

Here's what you need to understand when playing with and against MtG cards with the mutate keyword: Mutating creatures don't enter the battlefield If you cast a creature for its mutate cost and it successfully mutates, it isn't considered to have entered the battlefield