Six

Six is OPTIC's doctor and one of the one of the antagonists of A Trick of Light.

Description
"For God's sake, please, no pouncing."

- Six, as Olivia Park went insane in his car

As depicted, Six is haggard and possesses refined teeth; his appearance is deceptive, as he is extraordinarily quick and well-rounded in combat.

Chilling and impassive, Six serves his OPTIC superiors without question, taking merciless pleasure in experimenting on living beings. Obsessed with hybridization, Six regularly collects and alters individuals he deems desolate in life and transforms them into hybrid creatures, believing they are better this way than they were as humans, and treats them as his "children" within his metaphorical "garden". Six sees no problem with his art and dismisses other's objections to it as merely being unable to understand it. Despite this however, he does have a distorted sense of a physician's duty of care, always explaining to his patients what he is about to do to them, albeit regardless of whether they can comprehend what he says.

A Trick of Light
Six was employed on retainer as Olivia Park's personal surgeon, installing implants and modifications to her body as she became increasingly bionic. When OPTIC captured Cameron Ackerson, Six was ordered to prepare for his interrogation, and after attempting to reassure Cameron, quickly set about the interrogation via lie detector, searching for information about Nia. Six then offered to employ them both at OPTIC, and to Cameron's accusation of kidnapping, Six assured him that they were primarily an office, offering to manipulate elections and world affairs as paid services. Cameron however, hacked the office's networks, much to Six's amazement, and hacked the cameras to upload a video of their entire conversation to his YouTube channels.

Becoming intrigued by Cameron's abilities, Six threw his tablet against the wall and shattered it, revealing to Cameron the contents of his "garden" and confirming Cameron's ability to talk to technology. However, Six was interrupted by the arrival of Xal in the body of Nadia Kapur, and when Six attempted to prevent their departure, Cameron escaped in the confusion.

Alone with Xal, Six knew immediately that she was not human, deciding that she was much more interesting than Cameron. He offered to trade data on Cameron with her, and when she attempted to spit on him with acidic saliva, Six deftly dodged and became even further intrigued. He queried her repeatedly before "offering" to take her eyes for study, assuring her that she'd look "lovely, all unwound and scattered in my garden", and eventually Six attacked Xal, dodging and fleeing from the room when she retaliated. When Xal pursued, Six attempted to attack her with an ax, but Xal managed to incapacitate him and spray acid onto his navel. Seemingly undone and about to be bitten in the eyes by Xal's fangs, Six miraculously sliced Xal's hand off with a concealed blade, seemingly unharmed as he rose to his feet with blade and ax in each hand. Grinning, Six watched as Xal fled before him in terror.

Despite his injured stomach, Six was later dispatched to recover Cameron, blasting Juaquo Velasquez aside with a force gun but becoming interested in the Inventor with them, another alien with a humanoid appearance. Suddenly however, his support helicopter plummeted into Lake Erie and Six himself was run over by his own self driving car. He then reported Cameron unrecovered, warning Olivia Park of Cameron's imminent arrival.

Accompanying Olivia to a rendezvous point (against his wishes to probe Cameron and the Inventor), Six was unnerved to see Olivia contradict the orders she had just issued, ordering that they turn around and head to the I-X Center. He attempted to restrain her, but she launched herself out of the moving car, forcing him to follow her to the I-X Center. There, he found Xal's corpse, and excitedly brought it back to OPTIC headquarters.

Bemoaning the misuse of his talents and wishing instead that he was in his garden creating a human-salamander hybrid, Six set about dissecting Xal. He used electrodes and a chemically pliant human test subject to retrieve data from Xal's brain, gleaning the location of her spaceship, but also how she was able to hack and hijack human bodies, and the fact that she signaled for the rest of her race to come to Earth before she died.