gt card sleeves 600 Pack Clear, Perfect Fit Inner Sleeves Ideal for Double-sleeving, Trading Card Sleeve Compatible with MTG, PKM, TCG and Gaming Cards (60 Microns) : Toys & Games and smooth play Ryker | The Great Dalmuti

Dark Ritual and Cabal Ritual are fairly nice for a burst of extra mana for an explosive turn like a turn two K'rrik, Son of Yawgmoth

Puresteel Paladin

I anticipate ending up with some Lorcana cards in the future as a Disney fan, but its not something I would speculate in

To win, you can attack with your smaller creatures while building your mana to cast your expensive cards, and win via a massive Shivan Devastator, Tyrant of Kher Ridges, or Dragonwing Glider

The tiny opportunity cost means you may not need a heavy defender theme to make Coral Colony viable, but it obviously helps and also provides another way to kill opponents using Axebane Guardian + High Alert untap loops