Welcome to BCU
The main in-game "resource" is Cuties. Everything is centered around Cuties - they are the ones you breed, grow, send to adventures, send into raids, buy, sell, and trade on the marketplace.
Every Cutie can gain experience, level up, and use items, including those items that can improve its cooldowns and even its genes. All important Cutie attributes are stored on the blockchain as compactly as possible, keeping the transaction cost in mind.