Each other nontoken creature you control enters with an additional +1/+1 counter on it.
, : Proliferate X times, where X is the number of nontoken creatures you control that entered this turn. (To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there.)
Tromell is a mono-green +1/+1 counters engine: every nontoken creature you cast enters bigger, then you proliferate based on how many creatures hit the battlefield that turn to snowball counters across your whole board. You ramp into a wide, oversized creature base, activate Tromell each turn to multiply counters, and close with overwhelming stats or counter-based payoffs.
Free anthem effect that scales every nontoken creature you play, no setup required.
Repeatable proliferate gives access to counter synergies far beyond +1/+1 (loyalty, charge, infect, experience).
Cheap 3-mana commander that's easy to recast and immediately impactful.
Mono-green gives consistent ramp and resilient mana, supporting a flood of creatures.
A single board wipe undoes huge counter investment.
Tromell himself is fragile and a tempting removal target; without him the engine stalls.
Mono-green lacks interaction, card-draw fixing, and ways to break parity in stax/control matchups.
Proliferate only triggers on creatures that entered that turn, so go-wide flickers and token strategies don't fuel it.
Turns proliferate into a poison clock, giving the deck a fast alternate kill.
Add counter doublers (Hardened Scales, Branching Evolution, Doubling Season) and protection (Heroic Intervention, Bolster effects, The Ozolith) to make the engine resilient. Tighten the mana with fast green ramp (Sol Ring, Three Visits, Nature's Lore) so you deploy multiple creatures per turn to maximize proliferate. For higher power, lean into an infect package or a Craterhoof/Pathbreaker Ibex finisher to convert your counter advantage into immediate lethal.
Legendary Creature — Elf Advisor
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: Proliferate X times, where X is the number of nontoken creatures you control that entered this turn. (To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there.)