Opal is just a stone. However, it is said that owning it is like owning a rainbow, showing an infinite possible future.
It is believed that there are three kinds of monsters (things that look like gods) in the world, with different colors and properties.
Those that are black are called "Xuanyun"; those that are as clear as crystal are called "like water"; those that shine like fire are called "Red Flame".
If you gather all three, you will see eternal happiness.