Gems are the so-called "premium" currency that can be obtained during gameplay or by spending real money. You can use it to speed up the timer on a box or get the required amount of gold to fuse parts.

There are several ways to obtain gems: 

1. Open boxes

Tap on the box and open it. Opening the boxes will provide you with parts, gold, and a certain amount of gems. You can get the gems from the following boxes:

  • Super Box (Blue Box)
  • Legendary Box (Gold Box)

2. Complete Stages

You can obtain gems by completing Stages. Whenever you are promoted into the next Stage, you get Rating, Skill Points, Gold and Gems if your results were good enough.

3. Visit the store

Tap on the "+" icon near the Gems icon to buy more Gems for real money. (You can find out how to disable in-app purchases in the Billing section.)