Darkness is a synthetic substance created by Morqa Flowe. Its function is to calm and negate the effects of Light without actually destroying it (hence, the name). While not the true opposite of Light like Chaos is, it serves a more practical function in terms of research.
Morqa teaches each of his pupils to use Darkness, as they work with Light extensively in the Sea Lab Colony. Varios was created with the Darkness Talent gene spliced into him, so he has full control over Darkness, and uses it as his primary Talent.
Traits and Uses
Darkness is a black, goopy substance. When adapted to the host body, it finds host cells and uses them to reproduce. Thanks to this, a Darkness-user can harness the substance's energy by expelling Darkness out into the world without losing it completely (it constantly regenerates in the body).
It is most commonly used to travel in "dark puddles." The user sinks into a vat of Darkness, and can dart around through the world (and typically through solid objects) with ease. This allows Darkness users a sort of quicker travel, though it does have its limits. Using a dark puddle expends much of the Darkness available in the individual, and s/he will be unable to harness Darkness for some time afterward.
Other than dark puddles, Darkness' only other real use is to make Light return to its dormant state. This is most easily done with a spray of dark goop from the individual.
It should be noted that Darkness is not any sort of "evil" or particularly "dark" thing; it is only a man-made substance used to aid in the study of Light. It is so-named to imply that the substance is a "Light-stopper," and it is colored with such a deep black to prevent any mistaking of what the substance is.