Thalassophobia (EDH / Commander)

This is an optimized casual deck (power level 6-7) that seeks to win through enormous sea monsters and mana acceleration.

We have four win conditions:

• Kill people with combat damage. This is much easier if people at your table are suffering incidental damage (hopefully there's another combat-based deck!), and much harder if people are gaining life.
• Kill people with Arixmethes and an infinite mana. We generate infinite green mana by putting Freed from the Real or Pemmin's Aura on our commander, or infinite colored mana if we put them on Fatesticher or Kiora's Follower in conjunction with a land/artifact that taps for 2+ colored mana. We can use that infinite mana to kill someone with Stroke of Genius (i.e. draw their entire deck) or to pump Arixmethes to 21/3 with Pemmin's Aura and kill someone through commander damage. The combo kill is our fallback plan if someone at the table is gaining life or fogging combat (i.e. recurring Spore Frog).
• Kill people with infect damage. Grafted Exoskeleton lets a lot of our leviathans instantly kill people, and we're very good at removing blockers.
• Win through Jace's ultimate. We can ultimate Jace the same turn we play him if we can also play Deepglow Skate (10 mana, all told). Once you have Jace's emblem, it shouldn't be too hard to close out the game.

We're playing a lot of suboptimal cards because they're awesome. We're ignoring easier combo-wins because we're not playing Thrasios; if we wanted to combo off with ease, we wouldn't be jamming leviathans.

To comment on a few inclusions:

• Jin-Gitaxias, Core Augur is a mean card for mean people. Try to play it when you have up Fierce Guardianship, Narset's Reversal, or Mana Drain.
• Aethertide Whale, Colossal Whale, Great Whale, Pearl Lake Ancient, and Tromokratis are only here because they fit the theme. Swap them out for more interaction (e.g. Swan Song, Force of Will) or better creatures (e.g. Bane of Progress, Vorinclex) if your playgroup is more competitive.
• Dulcet Sirens are thematic and fun. Drop them for better cards if you don't like their aesthetic.
• If someone in your playgroup runs land destruction, don't play Lotus Vale.