Guildmage

Click here for visual deck (with images)
Click here for my EDH Commander decks
 
This idea started with me trying to put all the Guildmages in a single deck, with ways of generating tons of mana (e.g. Mana Echoes), and helper cards like Training Grounds.
I made sure each of the Guildmages had something to do (e.g. I put in cheap instants/sorceries for Izzet Guildmage).
I use Sliver Queen to help generate tons of mana (the tokens can be used with Earthcraft or whatever). There is a fair amount of potential for this deck to go infinite, so be warned if you find that sort of thing distasteful.
Yeah, I know I use Sliver Queen in a lot of my deck designs, but for this deck it is really helpful. (In fact, this was the deck that caused me to re-evaluate the need for 5 color / Sliver Queen in a lot of my other theme decks.)
 
Mana Acceleration (11): General (1): Spells (22): Sideboard (Omitted/Cut card ideas):
1 Chromatic Lantern 1 Sliver Queen 1 Ashnod's Altar 1 Carnage Altar
1 Gemstone Array   1 Heartstone 1 Fresh Meat
1 Gilded Lotus Creatures (31): 1 Illusionist's Bracers 1 Battle Hymn
1 Sword of the Animist 1 Azorius Guildmage 1 Rings of Brighthearth 1 Bonesplitter Sliver
1 Mirari's Wake 1 Boros Guildmage 1 Sword of Feast and Famine 1 Elspeth Tirel
1 Collective Voyage 1 Dimir Guildmage 1 Aura Shards 1 Nullmage Shepherd
1 Druids' Repository 1 Duskmantle Guildmage 1 Deflecting Palm 1 Skullclamp
1 Mana Reflection 1 Golgari Guildmage 1 Demonic Tutor 1 Slate of Ancestry
1 Explosive Vegetation 1 Gruul Guildmage 1 Training Grounds 1 Mirrorweave
1 Kodama's Reach 1 Izzet Guildmage 1 Twincast 1 Parallel Evolution
1 Cultivate 1 Korozda Guildmage 1 Bear Umbra 1 Intruder Alarm
  1 New Prahv Guildmage 1 Berserk 1 Haze of Rage
Lands (35): 1 Nivix Guildmage 1 Doubling Season 1 Coalition Relic
1 Arcane Sanctum 1 Orzhov Guildmage 1 Earthcraft 1 Darksteel Ingot
1 Crumbling Necropolis 1 Rakdos Guildmage 1 Nature's Will 1 Kyren Negotiations
1 Jungle Shrine 1 Rix Maadi Guildmage 1 Parallel Lives 1 Citanul Hierophants
1 Savage Lands 1 Selesnya Guildmage 1 Perilous Forays 1 Skyshroud Claim
1 Seaside Citadel 1 Simic Guildmage 1 Regrowth 1 Vesuva
1 Opulent Palace 1 Skarrg Guildmage 1 Fork  
1 Sandsteppe Citadel 1 Sunhome Guildmage 1 Mana Echoes  
1 Nomad Outpost 1 Vitu-Ghazi Guildmage 1 Reverberate  
1 Frontier Bivouac 1 Vizkopa Guildmage 1 Cathars' Crusade  
1 Mystic Monastery 1 Zameck Guildmage    
1 Command Tower 1 Firewake Sliver    
1 Exotic Orchard 1 Harmonic Sliver    
1 Gaea's Cradle 1 Necrotic Sliver    
1 Reflecting Pool 1 Prophet of Kruphix    
4 Swamp 1 Synapse Sliver    
4 Island 1 Gemhide Sliver    
4 Forest 1 Reflex Sliver    
4 Mountain 1 Seedborn Muse    
4 Plains 1 Heart Sliver    
1 Sol Ring 1 Mentor of the Meek    
  1 Mirror Entity