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Blue Photon was a former member of the Department of Mary Sues, later operating independently. He participated in the events of the Reorganisation, some of which drove him insane (he got better, though was still quite a bit mad), and in the events of the Crashing Down. He was written by Huinesoron.
Physically, Blue was tall and rather pale, and as his name may suggest, had blue hair. It was not dyed, it was not 'Stu-ish; it was in fact perfectly normal for his home continuum. Tradition has it that those with blue hair are blessed with perseverance and faithfulness, which two traits describe Blue well. Before the Reorganisation he was fairly outgoing, if not exactly social, but after his reappearance he was erratic and prone to extreme suspicion.
Blue joined the Protectors in June, 1994 HST, accompanied by his cousin Tango Dioxide and girlfriend Imbolc Telyan. Their home continuum is an AU Earth not known to appear in any published work, and although the trio searched for it, they were not able to relocate it before the Reorganisation.
Blue played a critical role in the opening salvos of the Reorganisation, but was held prisoner by the DIS for almost all of the events that followed, only escaping at the end of the civil war between the DIS and the rest of the PPC. On being released, he attacked Twp'atwt, ripped out the pine marten's eye, and fled HQ into a canon world. The exact world was never specified, but was apparently heavily forested, judging from dialogue between Twp'atwt and himself.
About five minutes prior to the Black Cats reentering HQ in June, 2006, Blue found himself pulled through a plothole into the Tomb of the Unknown PPC Agent, where he encountered the ghost of Imbolc Telyan. The Cats appeared in the same location, and Blue was forced to flee into the main body of HQ. He was then encountered by several groups during the invasion, and killed Twp'atwt shortly after the armies of the Mysterious Somebody entered the complex. Near the end of the crisis, he was killed by Elanor Laison to protect her newly reformed sister, Ontic.