The Basics
Codex is an RTS-themed customizable card game. You build your deck as you play from a pool of cards in your "codex". You'll grow your economy by hiring workers, and spend the gold on summoning heroes, leveling them up, casting their spells, and building more and more powerful units.
Expansion: Blue and Black Factions
This expansion contains the 3 blue heroes from the Flagstone Dominion faction, the 3 black heroes from the Blackhand Scourge faction, and all their associated spells and units, and so on. You can combine these cards with the Starter Set, Core Set, and Whitestar vs. Vortoss expansion too.
This expansion requires the Core Set.