Energy crystals

Found only on Titan, energy crystals are a highly unstable form of power. Composed of the same substance as the electric lava that serves as the moon's oceans, the crystals form in the Fire God's lair, a system of caves beneath the temple of the astrologer priests.

The Transformers cartoon
Cosmos discovered the location of the energy crystals, however when he attempted to leave the region of Saturn, he was attacked and shot down by Astrotrain. When Astrotrain discovered that the locals worshiped him as a god, he had them start collecting the crystals, though they were meant to be taboo to the native. The astrologer priests even began attaching the smaller crystals to arrows for use as weapons. Omega Supreme nearly exhausted his energy reaching Titan, so Perceptor was forced to collect a number of the crystals to repower the giant. After the Autobots successfully defeated the Decepticons, Astrotrain responded by starting a chain reaction in the crystals. They subsequently exploded, destroying the entire island.