Biggs

Background
Biggs was an X5 that had managed to escape Manticore when Max destroyed the building. He was an old friend of Alec and had gone on missions with him, including one where both of them had sex with a woman named Lola during their off-hours. After Ames White made public the fact that Transgenics live among the common people, Biggs made his way to Seattle an Terminal City. Alec and Max helped Biggs obtain a job at Jam Pony where he worked with them as a bike messenger, though they had begun using motorcycles to make the deliveries.

Biggs, Alec, and Max frequently went around the city to search for transgenics and bring them to Terminal City. It was on one of these missions that an agent of White's located Biggs through the use of a heat detector, exposing his high Transgenic body temperature. He tried to evade White's men, and managed to do so, but some civilians spotted him and beat him to death before hanging him upside down in the streets. Alec and Joshua tracked down Biggs' murderers and beat them up, threatening to kill them if they didn't leave town.

Behind the Scenes
The writers originally planned to reintroduce Krit, but Joshua Alba was unavailable, so Biggs was created instead.