Crystal (Earth Wars)

A Quantum crystal is used to power the space bridge.

Transformers: Earth Wars

Both factions of Autobots and Decepticons need quantum crystals to power the space bridge. If the crystal holds the coordinates to a certain bot, there are higher chances of the bot appearing through the space bridge. It is possible for the Spacebridge to Glitch out and create an amalgamation/hologram of a pre existing bot. this causes them to either dissipate and turn into Spark and Energon, along with a set number of shards that create crystals for higher rating bots, or the amalgamation will become an existing duplicate of the bot that exists, just at a higher skill level.