Crystal

Crystals are seen in most Crash as an energy source, a lot like gems. They are used by Dr. Cortex from Crash Bandicoot 2: Cortex Strikes Back all the way to Crash Nitro Kart 2. In state of fact their are 25 slave crystals one master crystal and the super big power crystal (the mother of all crystals), these Crystals were mostly used for evil to control all of Dr. Cortex's machines and gadets