The Commander
At the beginning of combat on your turn, put a number of +1/+1 counters equal to Maester Seymour's power on another target creature you control.
: Monstrosity X, where X is the number of counters among creatures you control. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
Guide
Gameplan
Maester Seymour is a mono-green +1/+1 counters engine that snowballs your team into lethal creatures. Each combat he dumps counters equal to his power onto another creature, and his monstrosity ability scales with the total counters across your board—so you grow Seymour first, then pour counters into a single trampling threat. Win by going wide-and-tall with counter synergies or by stacking everything onto one carrier and swinging for the fences.
Strengths
- Self-sustaining counter loop: growing Seymour increases what he distributes each combat
- Monstrosity scales explosively once you have counters spread across creatures
- Mono-green gives the best ramp and counter support in the format
- Cheap commander (3 MV) that comes down early and starts working immediately
- Plays well with doublers and proliferate for runaway boards
Weaknesses
- The combat trigger only adds counters during your combat, so it's slow out of the gate
- Heavily reliant on Seymour staying on the battlefield—prone to commander tax and removal
- Mono-green lacks interaction; little answer to combo, control, or flyers
- Targets a single creature, so without trample or evasion you can get chump-blocked
- Wraths and board sweepers undo your invested counters in one turn
Key Cards
- Hardened Scales — Adds an extra counter to every placement, accelerating both Seymour's growth and his distribution.
- Branching Evolution — Doubles all +1/+1 counters placed, supercharging both the combat trigger and monstrosity.
- Doubling Season — Doubles every counter Seymour puts out, making his loop snowball out of control.
- Inkmoth Nexus — A manland that turns your stacked counters into a fast infect/poison kill or evasive carrier.
- The Ozolith — Banks all your counters when creatures die, protecting your investment through removal.
- Cathars' Crusade — Each creature you cast adds counters to the whole team, feeding monstrosity and Seymour's math.
- Inspiring Call — Cheap protection and card draw that scales with your counter-laden board.
- Vorinclex, Monstrous Raider — Doubles your counters while halving opponents', a brutal asymmetric upgrade to the engine.
Upgrade Path
Lean into counter doublers (Hardened Scales, Branching Evolution, Doubling Season, Vorinclex) and proliferate effects to make every combat exponential. Add protection like Heroic Intervention, Snakeskin Veil, and The Ozolith so a single wrath doesn't reset your work, plus trample/evasion enablers (Rancor, Inkmoth Nexus) to ensure counters convert to damage. Top it off with Craterhoof Behemoth or Overwhelming Stampede as a reliable finisher and ramp like Sol Ring and Three Visits to deploy Seymour ahead of schedule.
Core Cards
The most-played cards for this commander, built from aggregated deck data (the Mythic Graph). Build public decks to seed it.
Win Conditions
- ▸Pump a single trampling or evasive creature huge and swing for lethal commander damage
- ▸Go wide with a counter-laden team and finish with Overrun or Craterhoof Behemoth
- ▸Suit up an infect creature like Inkmoth Nexus and deal 10 poison fast
- ▸Overwhelming board presence after a few uncontested combat triggers
Archetypes
- +1/+1 Counters — His entire kit revolves around generating, distributing, and doubling counters across your board.
- Voltron — You can funnel all of Seymour's counters plus monstrosity onto a single evasive creature for a one-shot kill.
- Stompy / Go-Wide Aggro — Counter doublers and anthem effects let you flood the board with oversized creatures to overrun the table.
- Combo — Counter-on-attack triggers and infect/persist synergies enable deterministic kills with the right enablers.
Combos
- Maester Seymour + Sage of Hours
→ Infinite turns, Lock
- Maester Seymour + Crystalline Crawler + Aggravated Assault
→ Infinite colored mana, Infinite combat phases, Infinite untap of creatures you control
- Maester Seymour + Crystalline Crawler + Hellkite Charger
→ Infinite colored mana, Infinite combat phases, Infinite +1/+1 counters on creatures you control
- Maester Seymour + Crystalline Crawler + Najeela, the Blade-Blossom
→ Infinite colored mana, Infinite combat phases, Infinite +1/+1 counters on creatures you control
Combos via Commander Spellbook.
Related Commanders
Same color identity (G), by popularity.
