As you explore each of the game’s dungeon mazes, you level up by killing enemies and collecting crystals, like in the main game. This will unlock new cards. And as you explore more, you unlock ways to upgrade these cards or even combine them into more-powerful variants. All of these cards, many of which do damage but can also trigger other effects and bonuses, have a mana cost to play them. The cost ranges from zero to five or more, depending on various factors. You only have so much mana to use each “turn” during a battle. So you play a few cards, and once you’ve used up all your mana, played