Kefnet

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Click here for my EDH Commander decks
 
Kind of a middle-of-the-road general: If you want draw, there are better alternatives (e.g. Arcanis); if you want landfall, play Patron of the Moon. But I gave it a try.
- Copy his ability (Rings of Brighthearth, Bracers, Alhammarret's Archive, Thought Reflection)
- Make his ability cost less (Heartstone, Training Grounds)
- "Whenever you draw..." triggers
- Landfall triggers (not too much of that in mono-blue)
- Discard as A cost
- Mass destruction (since Kefnet is indestructible)
 
Mana Acceleration (12): General (1): Spells (30): Sideboard (Omitted/Cut card ideas):
1 Burnished Hart 1 Kefnet the Mindful 1 Alhammarret's Archive 1 Tomorrow, Azami's Familiar
1 Caged Sun   1 Boompile  
1 Extraplanar Lens Creatures (21): 1 Coercive Portal  
1 Gauntlet of Power 1 Flowstone Sculpture 1 Diviner's Wand  
1 Khalni Gem 1 Kozilek, the Great Distortion 1 Empyrial Plate  
1 Metalworker 1 Masticore 1 Ghirapur Orrery  
1 Sword of the Animist 1 Molten-Tail Masticore 1 Grimoire of the Dead  
1 Thought Vessel 1 Psychosis Crawler 1 Heartstone  
1 Thran Dynamo 1 Razormane Masticore 1 Illusionist's Bracers  
1 Unstable Obelisk 1 Walking Atlas 1 Nevinyrral's Disk  
1 Wayfarer's Bauble 1 Aeon Chronicler 1 Oblivion Stone  
1 Worn Powerstone 1 Alexi, Zephyr Mage 1 Rings of Brighthearth  
  1 Chasm Skulker 1 Seer's Sundial  
Lands (36): 1 Dreamscape Artist 1 Sword of War and Peace  
1 Myriad Landscape 1 Hisoka, Minamo Sensei 1 Venser's Journal  
1 Radiant Fountain 1 Overtaker 1 Worldslayer  
1 Reliquary Tower 1 Patron of the Moon 1 Archmage Ascension  
1 Sunscorched Desert 1 Roil Elemental 1 Chamber of Manipulation  
1 Terrain Generator 1 Soramaro, First to Dream 1 Commandeer  
1 Thawing Glaciers 1 Stronghold Biologist 1 Cyclonic Rift  
29 Island 1 Stronghold Machinist 1 Disrupting Shoal  
1 Sol Ring 1 Sturmgeist 1 Force of Will  
  1 Toothy, Imaginary Friend 1 Jace's Erasure  
  1 Waterfront Bouncer 1 Mind Over Matter  
    1 Misdirection  
    1 Overburden  
    1 Sphinx's Tutelage  
    1 Thought Reflection  
    1 Training Grounds  
    1 Words of Wind