The Imposter (PNX annual)

"The Imposter" was the first "annual" episode of. It was the first Star Trek: Phoenix-X entry for the Star Trek Online: Unofficial Literary Challenge Annual and was the only Star trek: Phoenix-X entry for the first of those unofficial challenges. It focused on Captain Oroku Seifer and the USS Ragnarok.

Summary
Captain Seifer discovers Tomsin faked his way into Starfleet and attempts to deport him, but is confronted by a quasi-energy microbe-infected twin brother also named Tomsin.