There are 6 levels to measure the perfection and strength of creatures. Each ZOAN will evolve in these 6 consecutive levels towards the last version.
Experience points (EXP) will be accumulated through the matches. ZOANs will level up when they reach the required EXP. The Zoans with higher rarity can accumulate EXP faster.
Creatures with higher evolution levels take precedence in Play-to-Earn operations. High-level ZOANs have a higher win rate, higher farming productivity, higher rewards from winning the battles, etc.
After hatching from an egg, ZOAN will have a random Rarity Level. ZOAN will be attached to this Rarity Level for life. There are a total of 6 levels arranged in ascending rarity: Common, Uncommon, Rare, SuperRare, Epic ,and Legendary.
Rarity Levels also affect the priority of ZOAN as evolution levels stat. Not only that, the Rarity Levels decide the max times that the ZOAN can participate in Fight Monsters.
ZOANs with higher rarity will have faster leveling up.
The rarer the creatures, the more turns for Fight Monsters.