Juan Juarez

Juan Juarez (assuming that is even his real name) is not a Centurion, Shadow or otherwise. Nonetheless he has shown himself to be capable of holding his own in a fight alongside some of them.

http://i.imgur.com/VZifYqJ.png

He is an assassin, with a curiously carefree and philosophical inclinations, though ultimately as coldblooded and professional as the rest of them. He has said that he despises people who cannot commit to a plan and even more so those who feel regret after following through with one. He appears to have his own odd sense of honour, though it may well be another one of his tricks; he is rather resourceful and good at improvising on the go when things diverge from the original plan. Unlike some professional killers, however, his ultimate motives might be less about money (though he does not disdain it) and more about some higher cause, an ideological agenda. He is heavily involved with revolutionary organisations of various sorts, as well as the likes of Masque - and Jacob London, who appears to have been a long-term employer in the past retaining some leverage in the present.

As for his background, he is clearly Mexican, but has come far from home. There is some indication that he used to be a school teacher (and indeed he retains some mentoring tendencies even now), but all his students were killed by General Jorge Maria Calatrava, a warlord in the Mexican Revolution, perhaps starting him on a road of enlightened, attachment-free political violence. But all that is as maybe and he might not even remember it now thanks to complicated fairy magicks.

The precise details of his involvement in the Saint Haven Incident remain unknown to most, even the protagonists, though they know more than many. He became associated with Masque and the Shadow Federation some time before the event and was sent to Alderley Edge on the former's behalf, to retrieve everything necessary for the creation of the elixir of life. His plans having been thrown off by the chaos caused by Dr. Methuselah, he ended up joining forces with the young Centurions to acquire the life-water hidden in the Wizard's Cave. By then he has grown somewhat disillusioned with Masque's goals, realising they were not so perfectly aligned with his own as all that (to say nothing of his own lack of faith in the desirability of immortality). After assisting the group in their cave raid (and building a certain rapport with Else Rommel of all people), he offered them a deal: he would take one of them as a "hostage" to the Shadow Federation's hideout, liberate Ray Freedom, and then work with them to take it down from within, while the other Centurions stormed it from outside. Group consensus gave the role of hostage to Viktor Vaughn. However, at the last moment - or more precisely when Merlin was handing out his boons in reward for their victory over Methuselah - Viktor decided to instead request a map with the kids' mentors' locations. Disappointed, Juan Juarez nonetheless got his own wish from Merlin on Else's recommendation - and used it to transport himself to Saint Haven, deliberately revealing the name of the Shadow Federation's stronghold to the Centurions in the process.

At some point between then and the Battle of Saint Haven, it seems likely that Jacob got in touch with Juan and briefed him on the updated plan against Saint Haven. Whether or not that happened then and not a little later, however, Juan was already set on carrying out his own plan to take down Masque. He shot down Else's plane when it approached the Saint Haven Citadel, faking her death and pulling her into the fortress' abandoned top level. After going downstairs to retrieve Ray Freedom and the Freedom Ray from Madam Czarna, he took advantage of his good knowledge of the structure's layout, going with Else to take out the Shadow Federation's muscle, James Burke, and then providing her with a key she would use to free the older Centurions.

Meanwhile Juan split away from Else to do something else. By then Masque, mistrustful of the assassin to begin with, had become convinced that he had been betrayed, and sent men to capture him; this they did, with the man's full cooperation, in the Citadel's dungeon, bringing him up to the inner sanctum where Masque was keeping Sarah Hayes. Juan did what he could to keep Sarah from joining Masque, and parried Masque's own inquiries into his actions. When the final battle with Masque began, he swiftly freed himself and disappeared in the confusion, coming back to help out the Centurions one more time after having secured a couple of mysterious briefcases that likely belonged to Masque. After saying his hesitantly-amiable goodbyes with Else and Manfred von Richthofen, the latter hinting at the Mexican's affiliation with Jacob, Juan Juarez took off into the sunset...