Each season features several unique rewards. In the Mermaid Season, you can obtain the following rewards if you have a Gold Pass:

Mermaid Stool (Level 20)

The mermaid stool allows you to collect 50 coins and 3 Diamonds every 5 hours.

The mermaid stool can be used up to 30 times, after which it becomes a decoration.

Mermaid Lamp (Level 45)

The mermaid lamp turns 1 stained glass into 25 diamonds in 3 hours.

You can use the lamp 30 times, after which it turns into a decoration.

Mermaid Dressing Table (Level 70)

The mermaid dressing table lets you play the match pair mini-game for 5 energy every 5 hours. You have 6 flips to find and match two identical tiles with a marine diadem.

Possible rewards from the marine diadem include 100 experience, 10 diamonds, and 1 banishing lamp. Some tiles also contain bonus rewards, such as diamonds, energy, or coins. The bonus rewards can only be claimed with the main reward – the marine diadem.

The mermaid dressing table can be used 30 times before turning into a decoration.

All players can also receive this special seasonal reward:

Mermaid Sofa (Level 70)

You can use 1 fruit cocktail on the mermaid sofa, and receive 15 Energy in exchange after 1 day passes. 

It can be used 30 times, after which it becomes a decoration.