Whenever a player casts a creature spell, you 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.")
Flood the board with cheap creatures—your own and your opponents'—to manufacture a steady stream of Mutagen tokens, then convert those artifact tokens into +1/+1 counters to grow a dominant board or feed counter/artifact synergies. You ramp early, deploy a counters payoff, and snowball every creature spell cast at the table into permanent stat gains.
Generates value passively off every player's creature spells, scaling hard in creature-heavy pods
Mutagens are artifact tokens, enabling artifact-sacrifice, Treasure-style, and affinity synergies on top of counters
Mono-green gives unmatched ramp and access to the best +1/+1 counter and trample payoffs
Self-sufficient engine that doesn't require your own spells to trigger
Slow to close games without a dedicated payoff—counters alone can be grindy
Mono-green lacks interaction, removal, and protection for the commander
Mutagen activation is sorcery-speed and one counter at a time, so it's mana/time intensive
Heavily reliant on board presence; a wrath sets you back badly
Converts your pile of counters into a fast infect/poison kill.
Add counter doublers (Hardened Scales, Branching Evolution, Doubling Season) and proliferate effects to make each Mutagen worth far more, then include resilience like The Ozolith and Heroic Intervention to survive wraths. Cap the deck with a decisive finisher—Craterhoof Behemoth, Pathbreaker Ibex, or Triumph of the Hordes—so your accumulated counters actually close games. Prioritize fast green ramp (Sol Ring, Carpet of Flowers, mana dorks) to deploy your engine and pay the sorcery-speed activation costs ahead of the table.
Legendary Creature — Lizard Mutant
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