Michelangelo, Mutant BFF is a uncommon Legendary Creature — Mutant Ninja Turtle card from Teenage Mutant Ninja Turtles (TMT), collector number 198. Current market price: $0.35 (foil $0.63), TCGplayer market prices via Scryfall.
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 "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")