Fish

Every fish has a rarity, from Common up to Mythic, and a grade from ★ to ★★★★★. Each species comes in 15 looks: five at ★, four at ★★, three at ★★★, two at ★★★★ and one at ★★★★★.

Whether you breed two fish or merge ten into one, the game picks the new fish at random. A fish’s rarity counts as a level, from 1 for Common to 5 for Mythic, and a goldfish counts as 0. The odds of what you get go by those levels.

How many fish you can show in your aquarium goes up with its level: 3 at level 1, up to 12 at level 10. Goldfish don't take up a spot. Mythic fish are large, and need an aquarium of level 4 or more.

Merging turns 10 fish into one new fish. You can't put in goldfish, locked fish or fish still on their cooldown after breeding.

The game averages the 10 fish’s levels and adds 1 to get the new fish’s level. A whole number means you know exactly what you’ll get. Anything in between can go either way: each 0.1 past the whole number is a 10% chance of the rarity above. For example, 7 Uncommon fish and 3 Rare ones average 2.3, so the new fish has a 70% chance to be Rare and 30% to be Legendary.

Since the lowest average is 1, merging never gives you a Common fish. The table below shows what each average can give.

You make a seasonal fish on the merge screen: pick Seasonal Fish and fill all 10 slots with the fish its recipe asks for. You can make them only while their season runs, by the game's own dates, and you can't trade one until its season ends.

The seasons so far:

• Season 1 (1 September 2026 to 4 October 2026): Frostblue Sunfish (seasonal), Limeback Sea Turtle and Matsuri Octopus.