Khaydarin crystal

Khaydarin Crystals are monolithic artifacts and psionic technology in the StarCraft universe.

They were used by the Xel'Naga to facilitate their genetic experiments in an unknown manner. They are also psi-active. The Protoss use them to strengthen their psionic bond and power their psionic technology.

A large amount of Khaydarin is present on Aiur, homeland of the Protoss, apparently left there by the Xel'Naga during their flight. Like all other Xel'Naga technology, it was heavily guarded by the Shelak Tribe. However, the Zerg were still able to obtain small amounts of the crystals.

Psionic Matrix
Protoss structures and units, to a lesser extent, draw their energy from a great psionic energy matrix that emanates from Aiur. While a Nexus provides a link to this matrix, Khaydarin Crystal-based Pylons are needed to actually tap into the energy required to provide psionic energy to new colonies. Each Pylon generates a short-ranged aura of energy, which can provide the power needed by structures and warp gates. If a Protoss building loses its connection to the Psionic Matrix, it will shut down until it is reconnected, and new units cannot be gated in if there is insufficient psionic energy to provide them with power.

The fate of these crystals are unknown since the evacuation of Aiur by the Protoss, along with the status of the Psionic Matrix.

To a limited extent, Terrans have been able to use Khaydarin Crystals to control Zerg - the most famous example being Alan Schezar's control of Zerg on Aiur.