Chorus of the Conclave

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Click here for my EDH Commander decks
 
Ramp up a ton of mana.
Lots of creatures that use +1/+1 counters for things.
There is a modular mechanic subtheme; it's amusing (especially when they "chain" with a Doubling Season out), but not 100% necessary.
 
Mana Acceleration (20): General (1): Spells (6): Sideboard (Omitted/Cut card ideas):
1 Caged Sun 1 Chorus of the Conclave 1 Sword of Feast and Famine 1 Planar Gate
1 Extraplanar Lens   1 Aura Shards 1 Semblance Anvil
1 Gauntlet of Power Creatures (37): 1 Bear Umbra 1 Cave of Temptation
1 Karametra, God of Harvests 1 Arcbound Crusher 1 Death's Presence 1 Sword of Truth and Justice
1 Mirari's Wake 1 Arcbound Lancer 1 Doubling Season 1 Greater Good
1 Boundless Realms 1 Arcbound Overseer 1 Nature's Will 1 Ajani, Valiant Protector
1 Goreclaw, Terror of Qal Sisma 1 Arcbound Ravager   1 Doubling Cube
1 Gyre Sage 1 Arcbound Reclaimer   1 Nissa, Worldwaker
1 Incubation Druid 1 Arcbound Slith   1 Skyshroud Claim
1 Mana Reflection 1 Arcbound Stinger   1 Trollbred Guardian
1 Marwyn, the Nurturer 1 Arcbound Worker   1 Smothering Tithe
1 Nissa, Who Shakes the World 1 Crystalline Crawler   1 Jiang Yanggu, Wildcrafter
1 Patron of the Orochi 1 Etched Oracle   1 Together Forever
1 Regal Behemoth 1 Hangarback Walker   1 Rishkar, Peema Renegade
1 Selvala, Heart of the Wilds 1 Mindless Automaton   1 Arcbound Fiend
1 Traverse the Outlands 1 Scrapyard Recombiner   1 Arcbound Bruiser
1 Vernal Bloom 1 Tetravus   1 Arcbound Hybrid
1 Viridian Joiner 1 Thopter Squadron   1 Magus of the Candelabra
1 Vorinclex, Voice of Hunger 1 Triskelavus   1 Primal Vigor
1 Zendikar Resurgent 1 Triskelion   1 Solidarity of Heroes
  1 Walking Ballista   1 Soul's Majesty
Lands (36): 1 Workhorse   1 Keeper of Progenitus
1 Savannah 1 Enduring Scalelord   1 Momentous Fall
1 Temple Garden 1 Bloodspore Thrinax   1 Gleam of Authority
1 Canopy Vista 1 Champion of Lambholt   1 Citadel Siege
1 Scattered Groves 1 Cultivator of Blades   1 Ajani, Mentor of Heroes
1 Gaea's Cradle 1 Fertilid   1 Temporal Aperture
1 Gavony Township 1 Fungal Behemoth   1 Candelabra of Tawnos
1 Krosan Verge 1 Kalonian Hydra   1 True Conviction
1 Mosswort Bridge 1 Loyal Guardian   1 Staff of Domination
1 Myriad Landscape 1 Mycoloth   1 Tempt with Glory
1 Thawing Glaciers 1 Renegade Krasis   1 Gilded Lotus
1 Windbrisk Heights 1 Servant of the Scale   1 Sporeback Troll
20 Forest 1 Vastwood Hydra   1 Ulamog, the Infinite Gyre
4 Plains 1 Vigor   1 Ooze Flux
1 Sol Ring 1 Kinsbaile Borderguard   1 Earthcraft
1 Mana Crypt 1 Mikaeus, the Lunarch   1 Land Tax
  1 Shalai, Voice of Plenty   1 Mycosynth Golem
  1 Shinewend   1 Oblivion Stone
  1 Twilight Drover   1 Crowned Ceratok