This is a four-color control deck built around Jace. Jace's +1 is a steady card-selection engine, and his built-in attack tax plus a pile of Propaganda-style effects keep him alive. Counterspells, spot removal and token-making sweepers hold the board. Jace's −3, along with mass polymorph effects, turns cheap tokens into huge creatures pulled from a creature suite made almost entirely of 7-8 mana bombs. Meanwhile, noncreature-spell payoffs turn the steady stream of instants into cards and flying threats. How it wins: It locks down the table, then converts disposable tokens into free 7-8 mana titans like Archon of Cruelty, Archfiend of Despair, Avacyn, Hullbreaker Horror and Absolute Virtue, which close the game in the air. Key roles: - Attack taxes and planeswalker defense: These stack with Jace's own opponent-turn {2} tax so opponents struggle to pressure him or the player while he keeps ticking up for card selection (Propaganda, Ghostly Prison, Sphere of Safety). - Token fodder for polymorph: Cheap tokens and token-making spells, including sweepers that leave a board behind, supply the bodies that Jace's −3 and the mass-exile effects trade for real creatures (Lingering Souls, Martial Coup, Secure the Wastes). - Polymorph cheat into fatties: Jace's −3 and mass exile-and-reveal effects flip worthless tokens into the deck's few, oversized creatures, putting them onto the battlefield without paying their mana costs (Mass Polymorph, Synthetic Destiny, Nissa, Leyline Tamer). - Big creature finishers: A dense top end of game-ending creatures that is meant to be cheated in rather than cast, each able to dominate or lock the table on its own (Archon of Cruelty, Avacyn, Angel of Horror, Hullbreaker Horror). - Counter wall and interaction: A heavy suite of counterspells, spot exile and resetting wraths protects the engine and the cheated threats while answering opponents' bombs (Counterspell, Dovin's Veto, Farewell). - Spellslinger value payoffs: Casting cheap instants and card selection fuels enchantments that draw or make flying Sharks off every noncreature spell, plus artifacts that convert token creation into cards (Whirlwind of Thought, Shark Typhoon, Staff of the Storyteller).

Polymorph decklist

• 3× Island
• 2× Mountain
• 2× Plains
• 2× Swamp
• Arcane Signet
• Command Tower
• Fabled Passage
• Swan Song
• Brainstorm
• Chromatic Lantern
• Counterspell
• Fact or Fiction
• Lingering Souls
• Negate
• Path to Exile
• Propaganda
• Sol Ring
• Swords to Plowshares
• Spell Pierce
• Fellwar Stone
• Dimir Signet
• Exotic Orchard
• Underground River
• Path of Ancestry
• Ghostly Prison
• Prairie Stream
• Sulfurous Springs
• Shivan Reef
• Martial Coup
• Kher Keep
• Archfiend of Despair
• Rakdos Signet
• Dig Through Time
• Izzet Signet
• Disallow
• Azorius Signet
• Fetid Heath
• Sunken Ruins
• Mystic Gate
• Battlefield Forge
• Caves of Koilos
• Render Silent
• Talisman of Progress
• Drowned Catacomb
• Glacial Fortress
• Mass Polymorph
• Talisman of Dominance
• Reflecting Pool
• Despark
• Dovin's Veto
• Dreadhorde Invasion
• Talisman of Creativity
• Flawless Maneuver
• Talisman of Indulgence
• Isolated Chapel
• Sphere of Safety
• Ponder
• Synthetic Destiny
• Shark Typhoon
• Whirlwind of Thought
• Elspeth, Sun's Champion
• Secure the Wastes
• Nezahal, Primal Tide
• Clifftop Retreat
• Sulfur Falls
• Proteus Staff
• Expressive Iteration
• Serra's Emissary
• Archon of Cruelty
• Hullbreaker Horror
• Occult Epiphany
• Farewell
• Grand Crescendo
• Currency Converter
• Skrelv's Hive
• White Sun's Twilight
• Staff of the Storyteller
• Sunfall
• Stroke of Midnight
• Restless Spire
• Restless Anchorage
• Brainsurge
• Contaminated Landscape
• Perilous Landscape
• Windcrag Siege
• Absolute Virtue
• Radiant Summit
• Fatehold Annex
• Stingerquill Annex
• Nissa, Leyline Tamer
• Avacyn, Angel of Horror
• Turbulent Shore
• Turbulent Crater
• Turbulent Wetlands