Chasm Skulker is the star player in this deck, the Flying Spaghetti Monster himself. Gets bigger the more cards I draw, with a guaranteed +1/+1 every turn. Fantastic synergy with Abzan Falconer and Ordeal of Thassa, and once it gets going its very hard to stop, because even if you manage to get around my 8 protection spells, even if you kill it, it generates tons of babies. This card is simply awesome.
Phalanx Leader: The quintessential Heroic playmate. Crappy body, but gives counters to everybody.
Battlewise Hoplite: A nice heroic card that interacts with the numerous targeting spells in the deck. He makes his own +1/+1 counters when targeted, as well as letting me get some free scrys. At worst he's a 2/2 for two, so that's never bad anyway.
Abzan Falconer: Grants most everybody flying for 3 mana. Hells yes.
High Sentinels of Arashin: The aerial heavy-hitter. Gets bigger the more guys have counters, and makes his own using extra mana lying around.
Defiant Strike: Triggers heroic, draws a card (which triggers Chasm Skulker) and gives +1/+0
Aqueous Form: Triggers heroic, makes my squid unblock able, and free scrys for 1 mana.
Ordeal of Thassa: This thing has sickening synergy with this deck, particularly Chasm Skulker and Battlewise Hoplite. Buffs my creatures and gives me cards for two mana, which in turn buffs Chasm Skulker.
Feat of Resistance and Gods Willing: The protection spells; stops spot removal, prevents blocks, triggers heroic, and lets me either get a free +1/+1 counter or scry.
Triton Tactics: in a format where aggro and burn seem to be freaking everywhere, it never hurts to have a bit of extra toughness, not to mention that it gives me surprise blockers that freeze who they block, triggers heroic and interacts beautifully with outlast.
Military Intelligence: Honestly, this thing is incredible in any blue deck with consistent attacking, and when Chasm Skulker is around it's even better.