This is a five-color artifact deck. Its engine is filling the board with artifacts, ideally colored ones, then re-triggering enter-the-battlefield effects. Karn, Gilded Guardian draws a card for each color among other artifacts on entering. Colored artifact creatures, all-color effects and flicker or end-step blink effects turn Karn and the deck's value creatures into repeatable card advantage, with Panharmonicon doubling those triggers. Cost reducers, affinity and improvise let the artifact count snowball into card draw, token makers and creatures that scale with the number of artifacts. How it wins: It goes wide and tall with artifact-scaling creatures and Construct tokens, then pushes through damage with mass pump, evasion and Alibou's tapped-artifact burn, or drains with Tezzeret, Master of the Bridge. Key roles: - Color density for Karn's draw: Colored artifacts and effects that make permanents every color maximize the cards Karn, Gilded Guardian draws, and also fuel multicolor and per-color payoffs. (Leyline of the Guildpact, Transguild Courier, Chromatic Orrery) - Blink and ETB doubling: Instant and end-step flicker effects re-run the enters-the-battlefield triggers of Karn and the value creatures, and the doubler multiplies each entry. (Panharmonicon, Teleportation Circle, Ghostly Flicker) - Artifact cost reduction and cheap mana: Mana rocks, artifact lands and artifact discounts dump the hand quickly and push the artifact count high for affinity and improvise. (Etherium Sculptor, Foundry Inspector, Urza, Lord High Artificer) - Cast-trigger engines and copies: Casting artifact spells draws cards, makes Drone tokens or copies the spell, so every cheap artifact grows the board and the hand. (Iron Man, Bleeding Edge, Pinnacle Emissary, Uthros Research Craft) - Artifact-scaling threats and tokens: Construct tokens and creatures whose size counts artifacts become huge, Spacecraft get crewed into evasive threats, and stationing feeds them. (Urza, Chief Artificer, Simulacrum Synthesizer, Infinite Guideline Station) - Finishers and board-wide pushes: Mass pump, granted flying or trample, haste, and artifact-count damage turn a wide artifact board into lethal. (Craterclaw Colossus, Alibou, Ancient Witness, Cyberdrive Awakener)

Karn, Gilded Guardian decklist

• Ancient Cornucopia
• Arcane Signet
• Chromatic Lantern
• Chromatic Orrery
• Conjurer's Closet
• Cranial Ram
• Cursed Mirror
• Fellwar Stone
• Infinite Guideline Station
• Inspirit, Flagship Vessel
• Mox Opal
• Panharmonicon
• Sculpting Steel
• Simulacrum Synthesizer
• Sol Ring
• The Mind Stone
• The Soul Stone
• Thought Vessel
• Unwinding Clock
• Uthros Research Craft
• Ancient Den
• Arid Mesa
• Breeding Pool
• City of Brass
• Command Tower
• Exotic Orchard
• Flooded Strand
• Forest
• Godless Shrine
• Great Furnace
• Hallowed Fountain
• Inventors' Fair
• 2× Island
• Mana Confluence
• Misty Rainforest
• 2× Mountain
• 2× Plains
• Polluted Delta
• Reflecting Pool
• Reliquary Tower
• Sacred Foundry
• Scalding Tarn
• Seat of the Synod
• Spire of Industry
• Steam Vents
• Stomping Ground
• Swamp
• Tree of Tales
• Urza's Saga
• Uthros, Titanic Godcore
• Vault of Whispers
• Watery Grave
• Windswept Heath
• Alibou, Ancient Witness
• Baleful Strix
• Breya, Etherium Shaper
• Brightglass Gearhulk
• Craterclaw Colossus
• Cyberdrive Awakener
• Enthusiastic Mechanaut
• Esper Sentinel
• Etherium Sculptor
• Ethersworn Canonist
• Foundry Inspector
• Iron Man, Bleeding Edge
• Kappa Cannoneer
• Karn, Legacy Reforged
• Mendicant Core, Guidelight
• Noxious Gearhulk
• Phyrexian Metamorph
• Pinnacle Emissary
• Pyrewood Gearhulk
• Riptide Gearhulk
• Sharuum the Hegemon
• Thought Monitor
• Transguild Courier
• Twitching Doll
• Urza, Chief Artificer
• Urza, Lord High Artificer
• Voyager Quickwelder
• Fateful Discovery
• Leyline of the Guildpact
• Teleportation Circle
• Cloudshift
• Counterspell
• Dispatch
• Ephemerate
• Ghostly Flicker
• Heroic Intervention
• Swords to Plowshares
• Tezzeret, Master of the Bridge
• Fabricate
• Farseek
• Organic Extinction
• Thoughtcast
• Swamp