There are different types of fish rarity in the game. Each is represented by a specific lure color:
• Grey: Common – these fish can be upgraded up to level 12 • Blue: Rare – these can be upgraded up to level 11 • Green: Epic – these fish can be upgraded up to level 9 • Purple: Mythical – these can be upgraded up to level 8 • Gold: Legendary – currently the rarest lure in the game. These fish can be upgraded up to level 6
Each rarity type has a different upgrade price. The chance to find them in packs also differs.
Once you have upgraded a lure to its maximum level, you can sell the same type of lures should you get more from future packs.