Energon

Energon (エネルゴン, Enerugon) is the preferred fuel of the Transformer race. It takes many forms, including ore, crystal, gas, and raw energy, but it is most commonly used by Transformers in its liquid state, which is stored in many different mediums, most famously the energon cube. It is ubiquitous in Cybertronian culture; in addition to being the Transformers' primary "foodstuff", it also serves as the default power source for their machines and weapons, and is even used as a currency, a catch-all fuel of life, technology, war and commerce on Cybertron and beyond. This widespread use also comes in defiance of its extreme volatility: energon is prone to detonating explosively if mishandled, and is even used as ammunition in order to exploit this attribute.

True energon is an emanation of Primus, the creator-god of the Transformers, and is, in its most rareified state, the basic building block of Transformers' bodies and sparks. A highly coveted substance, it is sometimes capable of inducing remarkable transformations in Cybertronians, reshaping and otherwise altering their bodies while imbuing great strength and other powers, either temporary or permanent depending on the duration or strength of exposure. True energon is, however, extremely rare: in most universal streams, the Transformers' long war has left Cybertron drained of all but the smallest fraction of the substance, and although it has been known to exist on a small sampling of other planets throughout the multiverse (usually Earth), its paucity leaves the Transformers usually subsisting on artificially-generated substitutes created from other local energy sources.

"They're all after this stuff called Energon, which is kinda like food and gas and blood and electricity all mixed into one."
 * —About Energon.

Energon

 * Energon Crystals
 * Energon Cubes
 * Dark Energon