Opal Hunt is a special event that offers rewards for finding hidden treasures. When it is active, an icon with a blue gift box appears in the lower left corner.

Icon is the same as in Rune Hunt

Opals can be found in special chests on Endless Islands. 

To easily find a treasure chest with opals, tap the red opal with a question mark in the Hunt menu.

Gold Pass is a special feature that allows you to get better prizes for the Opal Hunt. Please note that the Gold Pass is valid for one hunt only.