Leviathans

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Big stompy fish!
A lot of Leviathans have really bad "enters the battlefield" abilities (sacrifice lands, give away your permanents, etc.), so I need to run a lot of Stifle effects here.
You'll see a lot of cards that try to get around these bad effects (Time Stop, Illusionary Mask, etc.)
Since I was already there doing the theme, and there's not quite enough Leviathans, I added in some other huge creatures with bad ETB abilities as well.
I also put in some mana cost 9 cards for Grozoth to find.
 
Mana Acceleration (13): General (2): Spells (19): Sideboard (Omitted/Cut card ideas):
1 Burnished Hart 1 Ikra Shidiqi, the Usurper 1 Akroma's Memorial 1 Decree of Savagery
1 Coalition Relic 1 Thrasios, Triton Hero 1 Crucible of Worlds 1 Vitalizing Wind
1 Gilded Lotus   1 Illusionary Mask 1 The Mimeoplasm
1 Thran Dynamo Leviathans (18): 1 Sundial of the Infinite 1 Artisan of Kozilek
1 Kiora's Follower 1 Eater of Days 1 Torpor Orb 1 Myojin of Seeing Winds
1 Fatestitcher 1 Nemesis of Reason 1 Kiora, Master of the Depths 1 Void Winnower
1 Tidewater Minion 1 Nimbus Swimmer 1 Voidslime 1 The Unspeakable
1 Boundless Realms 1 Simic Sky Swallower 1 Demonic Tutor 1 Tidespout Tyrant
1 Explosive Vegetation 1 Aethersquall Ancient 1 Plague Wind 1 Prophet of Kruphix
1 Mana Reflection 1 Breaching Leviathan 1 Rise of the Dark Realms 1 Teleport
1 Recross the Paths 1 Grozoth 1 Clone Legion 1 Staff of Domination
1 Skyshroud Claim 1 Inkwell Leviathan 1 Homarid Spawning Bed 1 Tidal Force
1 Zendikar Resurgent 1 Jokulmorder 1 Levitation 1 Bringer of the Blue Dawn
  1 Kederekt Leviathan 1 Quest for Ula's Temple 1 Sun Quan, Lord of Wu
Lands (36): 1 Leviathan 1 Stifle 1 Seedborn Muse
1 Underground Sea 1 Marjhan 1 Summary Dismissal 1 Colossal Heroics
1 Bayou 1 Pearl Lake Ancient 1 Time Stop 1 Demon of Death's Gate
1 Tropical Island 1 Segovian Leviathan 1 Trickbind 1 Spirit of the Night
1 Watery Grave 1 Sky Swallower 1 Whelming Wave 1 Isochron Scepter
1 Overgrown Tomb 1 Stormtide Leviathan    
1 Breeding Pool 1 Thing from the Deep    
1 Polluted Delta 1 Trench Gorger    
1 Verdant Catacombs      
1 Misty Rainforest Non-Leviathans (12):    
1 Opulent Palace 1 Leveler    
1 Swamp 1 Phyrexian Dreadnought    
6 Forest 1 Sire of Stagnation    
15 Island 1 Phage the Untouchable    
1 Thawing Glaciers 1 Arcanis the Omnipotent    
1 Terrain Generator 1 Archetype of Imagination    
1 Mana Crypt 1 Consecrated Sphinx    
1 Sol Ring 1 Denizen of the Deep    
  1 Polar Kraken    
  1 Wonder    
  1 Myojin of Life's Web    
  1 Whisperwood Elemental