Immortal Coil Immortal Coil provides a strange protection spell that effectively deflects damage from your face to your graveyard and keeps you alive for longer than you have any right to be, assuming you fuel it with cards like Cemetery Tampering and Mesmeric Orb
7 Hydroid Krasis Triple The Creature Types Blue and green decks love doing two things, making mana and drawing cards, and with Hydroid Krasis, you can do both while throwing in a little life gain on top
True, it's a six drop, but artifacts have Affinity enablers, and lands like Mishra's Workshop (Tap: Add CCC to your mana pool
They're not exactly cheap though - the bundles priced at $9.99 for four rare wildcards, and $19.99 for four mythics
Paired with cards like Ankh of Mishra or Dingus Staff, Dariens ability can get out of hand quickly