Nemesis was an operative of the Heroes Unite Initiative. The Commander viewed his unique abilities as a key advantage in the attempt to bring down Energize.
During his early days as a rookie with the Heroes Unite Initiative, Nathan underwent a training mission under SHELL's expert tutelage to bring the villain Rime into custody. Following this mission, SHELL's comment that Nathan was "every super-villain's personal nemesis" became the inspiration for Nemesis' hero name.
Nemesis crossed the line in his pursuit of Energize, ruthlessly murdering his girlfriend Misty as bait. The Commander's tacit support of this action was a key factor in her removal as HU Commander following the events of Energize: Hunted.
The HU Commander knows that at one point Nemesis was known as "Mimic", and this seems to be part of a past Nemesis would rather forget. It has now been revealed that through his conflict with Energize during the Energize: Hunted finale that Nemesis became the person known as The Stormfront by using his powers on the newly cosmic-powered Energize.
As such, preventing his rise to power is the reason Titan was sent back to this time. She used the Black Dawn on Nemesis and Energize while they were fighting. This stripped Nemesis of his powers as well as killing Michael Callahan (Energize) and dissipating the Energize Entity and stripping Angelblood (who was only caught in the peripheral blast) of the bulk of her Celestial might.
To activate his powers Nemesis needs to look into his opponents eyes. He will then develop whatever skills or abilities are necessary to counter theirs. A limitation of his power is that he cannot adapt to combat multiple skills simultaneously.
(Base Levels / Max Power Achievable)