Each creature you control with a counter on it can't be blocked by more than one creature.
Whenever Michelangelo enters or attacks, create a Mutagen token. (It's an artifact with ", , Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")
Build a wide board of creatures, load them up with +1/+1 counters using Mutagen tokens and other counter synergies, then push through with menace-style evasion since each countered creature can only be blocked by one creature. You snowball quickly in mono-green: ramp into Michelangelo, generate Mutagens each combat, and convert counters into a lethal alpha strike.
Free, repeatable counter generation that also pumps your team every turn
Built-in semi-evasion (one-blocker limit) that makes counters double as offense
Slots into the deep mono-green +1/+1 counter package with strong synergy payoffs
Cheap, recastable commander at 4 mana that keeps producing value if removed
Mono-green means no interaction, card draw fixing, or removal outside green's toolkit
Board wipes and mass removal can erase the counter-laden army you invested in
Counters can be answered by -1/-1 effects, proliferate disruption, or counter removal
Evasion only stops multi-blocks, so it doesn't beat fliers or single big blockers well
Legendary Creature — Mutant Ninja Turtle
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