The theme of this deck is mythical creatures (Phoenixes, Sphinxes, Djinns, Dragons, Krakens, Leviathans, etc.) I chose Niv-Mizzet as the general because there are only 3 options for UR and he is somewhat on theme. Jhoira would make sense but she would probably make everyone feel threatened and/or think I'm up to something, as I could definitely use her fairly well in this deck even if I'm not blowing up the world or anything.
Wow, those are some big dudes. It's too bad about Jhoira, as that she would really help you out a ton. Unfortunately, she does come with a big target painted on your forehead. Would people believe you if you told them you weren't playing Obliterate? Cuz you basically gotta get to 6 mana before you can make a board presence. Having half your deck be mana sources helps, but there has to be an easier way to get those guys out.
1 Niv-Mizzet, the Firemind
Lands (37)
1 Cascade Bluffs
1 Gemstone Caverns
16 Island
1 Izzet Boilerworks
11 Mountain
1 Reflecting Pool
1 Reliquary Tower
1 Scalding Tarn
1 Spinerock Knoll
1 Steam Vents
1 Temple of the False God
1 Terramorphic Expanse
Creatures (27):
1 Solemn Simulacrum
1 Djinn of Wishes
1 Kazuul, Tyrant of the Cliffs
1 Magma Phoenix
1 Serra Sphinx
1 Shard Phoenix
1 Spellbound Dragon
1 Sphinx of Lost Truths
1 Capricious Efreet
1 Drifting Djinn
1 Keiga, the Tide Star
1 Mahamoti Djinn
1 Rorix Bladewing
1 Ryusei, the Falling Star
1 Skarrgan Firebird
1 Sphinx of Jwar Isle
1 Djinn of the Lamp
1 Dragon Mage
1 Goliath Sphinx
1 Knollspine Dragon
1 Sphinx Ambassador
1 Bogardan Hellkite
1 Tidal Kraken
1 Tidespout Tyrant
1 Inkwell Leviathan
1 Deep-Sea Kraken
Artifact Mana (10):
1 Coalition Relic
1 Darksteel Ingot
1 Everflowing Chalice
1 Fellwar Stone
1 Gilded Lotus
1 Izzet Signet
1 Mana Vault
1 Mind Stone
1 Sol Ring
1 Thran Dynamo
Draw Spells (8):
1 Compulsive Research
1 Fact or Fiction
1 Merchant Scroll
1 Mystical Tutor
1 Rush of Knowledge
1 Thirst for Knowledge
1 Three Wishes
1 Wheel of Fortune
1 Arcane Denial
1 Counterspell
1 Cryptic Command
1 Suffocating Blast
Removal (6):
1 Chain Reaction
1 Comet Storm
1 Prophetic Bolt
1 Riddle of Lightning
1 Spin into Myth
1 Starstorm
Miscellaneous (7):
1 Aladdin's Lamp
1 Insurrection
1 Journeyer's Kite
1 Mana Flare
1 Mana Geyser
1 Propaganda
1 Rite of Replication
norbert88
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Other defensive stuff you may consider include Pendrell Mists, Aether Barrier, Embargo, Collective Restraint. Of course, most of these can hurt you as well.
Most recently looking at Morinfen!