In the simplest take on this ability, one may be capable of mirroring another's ability.
Nemesis (or Reactionary Replication) is a rare ability that functions primarily on the level of instinct, though once is discovered by the evolved human, can be function as part reactionary and part willful control. With this power a user can manifest a new ability to respond to any they detect through any line of sight or within a limited range. The mimicked power's alternative is instead gained and the user will find they can counter whatever power is exhibited in the original person's manifestation, such as gaining fire against an ice user or gravity powers against a flier.
This power is rarely found, and most often discovered among a rare and select few of specials who may never even know they have a power. Also, because of the unique nature of the power, no secondary ability manifests for those with this power. (Meaning one could not have Nemesis and Flight, etc..) With training, the Nemesis user can hold the copied power for up to one hour after replication (either way) but after that their slate will always go clean, leaving them powerless and "normal" once more. Most who have this ability, however, will lose the power(s) gained as soon as the threat passes or the other "special" is out of range.
A common flaw with this ability is that the user becomes dependent on using their power far too much and has a decreased ability to fight like a normal human, though this may not always be the case. Most oddly, this power cannot be used to duplicate or generate power negation. Similarly, powers that deal in mind control or puppetry can only be generated through the duplication, rather than creating it as a counter for another special.
NOTE: This power is currently Restricted in the Role Play.
This power cannot be replicated by any power farming ability.