Kathril fills the graveyard with creatures carrying many different keywords, then casts Kathril to hand out a keyword counter for each ability found there, growing Kathril with +1/+1 counters as it goes. Self-mill, cycling creatures and reanimation keep the graveyard stocked with keyword creatures. The deck then shares those keywords across its whole board and moves its counters onto the best attacker, turning a handful of bodies into evasive, double-striking, lifelinking threats. How it wins: It attacks with oversized, keyword-stacked creatures, often one huge flying, double-striking, trampling threat or a board granted every keyword at once, while goad auras and sweepers keep opposing creatures from blocking. Key roles: - Keyword stocking: These cards put creatures with many keywords into the graveyard so Kathril's enters trigger and the graveyard-keyword creatures reach their full value. Cycling creatures add a counter as they go to the graveyard. (Selective Adaptation, Splinterfright, Titanoth Rex) - Keyword payoffs: These creatures copy every keyword found in the graveyard or on the battlefield and spread them across the team. One keyword-rich creature or counter-laden body can give the whole board flying, double strike and lifelink. (Odric, Lunarch Marshal, Majestic Myriarch, Cairn Wanderer) - Counter manipulation: These cards add keyword and +1/+1 counters, then move them onto a single creature to build an unstoppable threat. They also draw cards when countered creatures leave, and Tayam spends counters to bring back cheap permanents. (Slippery Bogbonder, Nesting Grounds, Nikara, Lair Scavenger) - Recursion and recasting: These cards return keyword creatures, and the commander, to the battlefield or to hand. That allows repeated enters triggers and lets Kathril come back after the graveyard has grown. (Unburial Rites, Deadbridge Chant, Netherborn Altar) - Board control: Goad auras force opponents' creatures to attack elsewhere, and mass removal clears blockers while counters or indestructible keep the deck's own key threat alive. (Duneblast, Sunblast Angel, Predatory Impetus)

Symbiotic Swarm decklist

• Ajani Unyielding
• Tayam, Luminous Enigma
• Nikara, Lair Scavenger
• Yannik, Scavenging Sentinel
• Avenging Huntbonder
• Cartographer's Hawk
• Vitality Hunter
• Daring Fiendbonder
• Slippery Bogbonder
• Akroma, Angel of Wrath
• Angel of Finality
• Cataclysmic Gearhulk
• Kalemne's Captain
• Odric, Lunarch Marshal
• Reveillark
• Solemn Recruit
• Sunblast Angel
• Zetalpa, Primal Dawn
• Cairn Wanderer
• Soul of Innistrad
• Soulflayer
• Hornet Queen
• Majestic Myriarch
• Splinterfright
• Archon of Valor's Reach
• Karametra, God of Harvests
• Void Beckoner
• Titanoth Rex
• Aerial Responder
• Vampire Nighthawk
• Acidic Slime
• Sakura-Tribe Elder
• Satyr Wayfinder
• Skullwinder
• Nyx Weaver
• Selective Adaptation
• Ever After
• Duneblast
• Unbreakable Bond
• Unburial Rites
• Cultivate
• Harmonize
• Obscuring Haze
• Blood Curdle
• Abzan Charm
• Deathsprout
• Despark
• Grisly Salvage
• Netherborn Altar
• Mimic Vat
• Bonder's Ornament
• Arcane Signet
• Commander's Sphere
• Sol Ring
• Swiftfoot Boots
• Together Forever
• Abzan Ascendancy
• Deadbridge Chant
• Martial Impetus
• Parasitic Impetus
• Predatory Impetus
• Nesting Grounds
• Canopy Vista
• Caves of Koilos
• Exotic Orchard
• Gavony Township
• Grim Backwoods
• Sungrass Prairie
• Blighted Woodland
• Command Tower
• Golgari Rot Farm
• Krosan Verge
• Memorial to Folly
• Myriad Landscape
• Orzhov Basilica
• Sandsteppe Citadel
• Selesnya Sanctuary
• Blossoming Sands
• Evolving Wilds
• Jungle Hollow
• Scoured Barrens
• 3× Plains
• 2× Plains
• 2× Plains
• 3× Swamp
• 2× Swamp
• 2× Swamp
• 2× Forest
• Forest
• Forest