Play and win Versus matches to get Versus crystals. They reward you with gold or Battle Chips. Battle Chips can be spent on an Arena Crystal, which gives you a chance at getting a four-star Champion. You will earn a crystal every four hours of game play. It rewards you with consumables. Log in daily to get a free crystal. It rewards you with a two-star or better Champion. The purple crystals collected during quests have a variety of rewards, but the most common is ISO-8. Premium Hero crystals can be purchased with Units, the game's premium currency. These crystals will always result in a two-star Champion at the minimum.