The Rainbow Gem Tank is a tank that can be purchased from the Store for 600 Gems.
The Rainbow Gem Tank, similar to the othervariationsof thegemtanks, has an octahedronic shape. However unlike the other gem tanks, this gem tank is the combination of all of the 5 gem tanks and because of that, the tank will show all of the colors of the rainbow. There are black metal outlines surrounding the tank, and the top is dark purple.
While this tank has been in the game since launch, it did not have a shop picture until May 27, 2021.