Coins
Coins are obtained by winning Battles, playing Campaign mode, completing Quests, or through the shop. Coins are used to perform card upgrades and can also be used to purchase cards and Books. The option to purchase Coins using real money is always available and can be accessed by tapping the 'Shop' button in the main screen.
Rubies
Rubies are obtained by winning Battles and ranking up or through the shop. They can be used to purchase cards and Books.
Fusion Stones
Fusion Stones are obtained by winning Battles and they can be used to craft the cards needed to perform a card upgrade.