Spontaneous recoloration refers to the temporary or permanent alternation of a Transformer's exostructure, usually in response to an energy surge. Usually (but not always) this external color change signifies a higher energy-state within the Transformer's body accompanied by increased (or even entirely new) abilities.
Spontaneous recoloration is similar to reformatting. Unlike reformatting, which wreaks wholesale physical alterations to the transformer's physical form, recoloring is completely cosmetic.
For unknown reasons, spontaneous recoloration does not uniformly re-tint existing surface pigments, but may result in completely different color arrangements, or even add entirely new "badass" detailing, such as flames or racing stripes.