The cellar's emergency lights exploded overhead, and Erin tumbled over in a pile of glass slag. The blue light of the incubation chamber reflected the faces of hundreds of Cole, clones branded with "XIII" on their necks, umbilical cords connecting them to the central computer.
"Surprise?" Kayden's voice came over the loudspeaker. Erin looked up to see the surveillance probe spinning, and the screen suddenly lit up with surveillance footage from three years ago-the SUV she was driving was skidding on the highway on a stormy night, while two giant wolves tore up the cliffs in the distance.
"I was there." Kayden's face appeared on the surface of the clone incubation chamber, "Cole bit his father's throat, but the old Wolf King injected him with the transformation serum before he fell off the cliff."
Erin's scalpel suddenly stabbed into the main console slit, "So you stole the serum samples?" In a shower of sparks, she ripped out the data drive, "These clones are genetically marked with your DNA, Mr. FBI."
Alarms snapped and the clones opened their eyes in unison. Kayden's laugh was laced with an electric murmur, "Remember the medical school prom? You used to say that the perfect crime was for the killer to walk into the autopsy table himself."
Erin jerked back as the sharp claws of Cole's clone grazed her throat. She dodged between the incubation pods, suddenly noticing that all the clones had mechanical prosthetic eyes in their right eyes - in the exact same spot as Cole's injury.
"You want to create an army of obedient wolves." She leapt onto the console and inserted the hard drive into the sterilizer, "But forget that the wolf sense of smell can distinguish the metallic taste of a clone."
The top of the cellar suddenly collapsed as the hot steam erupted. The real Cole crashed down wrapped in flames, shrapnel embedded in his silver fur. The moment Erin caught him, she realized he was clutching half an FBI badge in the center of his paw.
"The helicopter has military biometric markings." Cole coughed up blue blood, "Kayden is no ordinary agent..."
The bolt sounded in the doorway. Kayden held up the modified Barrett, the barrel etched with cursed runes, "Honey, you always pick up stray dogs and bring them home." He kicked away the silver bullet casings at his feet, "But this time he picked up a biochemical weapon."
Erin suddenly ripped open Cole's blood-stained shirt to reveal the beating metal core of the heart. She stabbed her scalpel into the core connector the moment Kayden pulled the trigger, "Remember when you taught me to hack into pacemakers?"
The entire cellar was suddenly plunged into darkness. The clones let out a mournful howl, and Kayden's thermal imaging sights were haunted by the ghostly figure of Erin yanking Cole and leaping into the ventilation ducts.
"There's no escape." Kayden sneered into his communicator and detonated the pre-set explosives. As the wave of air toppled the ventilation ducts, Erin caught a whiff of the strange scent of Cole's blood - exactly the same as she'd smelled after the car accident three years ago.
They tumbled into the underground river, Cole suddenly pinning her against the rock wall in the turbulence, "You realized that already, didn't you?" His canines pierced his tongue and kissed her with blood, "My memory was tampered with..."
Fragmentary images exploded in Erin's mind: the altar in the moonlight, the holy tattoo on the back of the woman's neck, and the silver dagger that had pierced Cole's eye socket. Chills ran up her spine as she took in the face of the knife-wielder-it was twenty-year-old Kaiden.
"He gouged out my eyes." Cole's mechanical prosthetic eye flashed red, "In order to extract the purest Wolf King genes."
Erin's wristwatch suddenly beeped with a locator alert, a miniature tracker she had hidden in Cole's tail. Her pupils constricted when she read the coordinates of the location - the very same interstate highway bluff where they had first met three years ago.
Kayden's helicopter had hovered over the cliff edge. Erin crawls out of the sewer dragging an unconscious Cole, and the moonlight illuminates the scratches on the cliff face - two wolf paw prints crisscrossed in the shape of an X, exactly where Cole's father fell to his death.
"It's time for the game to end." Kayden tossed and played with the serum test tubes, "Give me Cole and you can still be chief medical examiner."
Erin suddenly laughed. She ripped open the collar of her shirt, revealing the bite mark just below her collarbone, "Are you sure you want to kill the only host who can harness the Wolf King gene?" As beads of blood oozed out, Cole suddenly twitched and opened his golden pupils.
Kayden's gun wobbled for a moment. Erin takes the opportunity to fling out her scalpel, the blade cutting through the helicopter sling with precision. As the cooler containing the serum plummets toward the cliff, Cole and Kayden simultaneously lunge off the edge.
"Grab on!" Erin whipped out her belt and wrapped it around Cole's ankle, clutching Kayden's watch chain in her other hand. The two men hung face to face under the night sky, the tip of Cole's claw against Kayden's throat, Kayden's gun pointed at Cole's brow.
"The serum kit has mother's DNA in it," Kayden suddenly shouted to Erin, "It can fix the werewolf genetic defect!"
Cole's laugh shook off the gravel, "So he didn't tell you? The woman torn apart by wolves twenty years ago..." Sharp claws slashed across Kayden's heart, revealing a mechanical heart glistening silver beneath the skin, "Long ago made into a biobot."
Erin's wristwatch sounded a piercing alarm. She saw the serum box's locator signal moving at the bottom of the cliff - something had caught the fall in the darkness.
"Father..." Cole hissed in sudden agony, his mechanical prosthetic eye bursting into flames. A familiar wolf howl came from the bottom of the cliff, a growl with an electronic remix shattering the helicopter's glass, "How do you like this engagement present, my good son?"
Kayden took the opportunity to break free of his restraints and fired a sleeve arrow into Erin's brow. As Cole curls his tail away from the concealed weapon, Erin suddenly lets go - both of them plummeting into the darkness at the same time while she tugs on the climbing rope and slides down the cliff, her white coat hunting in the night wind.
The luminescence of the cliff-bottom lab illuminates the horrific truth: the remnants of Kaiden's mother are attached to the incubation chamber, and the old Wolf King's mechanical wolf claws are caressing her face. Seven hollowed-out hearts beat in glass jars, each embedded with a replica of the Cole chip.
"Mage Erin, welcome to the resurrection ceremony." The old wolf king swiveled his neck, revealing golden pupils identical to Cole's, "This body you've chosen is indeed perfect - both a wolf saint and compatible with human technology."
Cole suddenly stepped in front of Erin, his mechanical prosthetic eye projecting a holographic image: twenty years ago, on the night of the full moon, Kaiden himself pushed his mother towards the wolves, while the old wolf king picked up the crying baby from a pool of blood - it was Erin with the holy tattoo on her neck.
"My dear, now do you see why you always manage to calm my rampages?" Cole's voice mingled with electronic murmurs, "Your blood neutralizes mechanical viruses..."
Kayden's bullet suddenly went through Cole's chest. As Erin catches his falling body, she realizes that he has half a wedding ring embedded in his mechanical heart - the very same one she returned that year.
"The surprise is always at the end." Kayden ripped off his shirt, revealing the exact same wolf branding as Cole, "We're the real twins, sister."