Perks are classified based on their rarity: Rare, Epic, and Legendary. Perks with higher rarity tend to give better effect.
Perk can be bought from the store. They can also be obtained from chests won in duels, booster packs, or as rewards after defeating opponents during main or side quests. If the players receive a perk they already have, a part of an upgrade bar will fill up. When the upgrade bar completely fills, the perk will be upgraded to the next power level, increasing its overall effectiveness. Better chests or booster packs may contain perks with higher rarity. As for the perks obtained from fights, players may get perks with random rarity - it is even possible to get a perk with Epic or Legendary rarity, but the chance is small.
Perk can be inserted into the equipment's slots to have them activate in fights. Because the number of slots are limited (3 at most), there is a limit to how many perks the player can have equipped at one time. Perks are restricted based on the type of equipment. For example, some perks can only be applied to weapons and cannot be used with armors and helms.