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Xander the Assassin

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Summary: An old artifact crosses dimensions after the death of its wielder to be rediscovered. A Master Assassin will join the fight against the darkness.

Categories Author Rating Chapters Words Recs Reviews Hits Published Updated Complete
Multiple Crossings > Xander-Centered > Theme: Heroic XanderDarlokFR18420,51066018,0506 May 1320 May 13No

Chapter One

Xander the Assassin

Disclaimer: I do not own Buffy the Vampire Slayer, Assassin’s Creed or any of the Marvel universe content used in this story. They are owned by people far more fortunate and creative than I am. This was written for enjoyment and no profit was made.

Summary: An old artifact crosses dimensions after the death of its wielder to be rediscovered. A Master Assassin will join the fight against the darkness.

Spoiler Alert: Before the story, all of the events of the Assassin’s Creed video games all the way till the end of Assassin’s Creed 3 took place.

Chapter 1

Venice, Italy ~ Year 2005

A dark haired and handsome young man removed the five hundred dollar sunglasses from his eyes as he rubbed the sleep from them. Straightening out his clothing, he was thankful the long flight was finally over when he made his way to customs. The airport was mostly quiet due to the lateness of the hour which gave a respite in dealing with the masses . The well dressed man in a custom tailored italian suit swiftly walked to the exits intending to get home to his family after having to be away for a week on business. Unfortunately his plans would be delayed due to the usual activities following one of his trips.

Nearby stood an older man in an off the rack suit that screamed law enforcement to anyone that paid attention. In the man’s hands he held a sign spelled in his name. The young man could only roll his eyes at the agent’s continual efforts to follow procedures. The nonthreatening individual had worked with the youth for many years. They knew who each other were but the the senior male liked his routines.

Outsourcing to a law agency was something he did on a whim wanting to see more of the world. Working a couple jobs a year gave him a reason to go to places he wouldn’t normally. After gaining quite a bit of notoriety in his line of work, the many terrorists and demons the world grew to fear him. He was the assassin that could ghost into almost anywhere and kill the untouchable. Those he couldn’t reach were the ones who basically built themselves their own prison around themselves in order to keep him away.

Shaking those thoughts from his mind, the youth went over to the nondescript older man and was handed a briefcase filled with precious metals and gems as a form of payment for services rendered.

“Your usual fee as promised Doctor Castle.” The youth gave a threatening look at being formally addressed. “Sorry, Alexander.”

Alexander ‘Xander’ Castle shook his head in annoyance at the genial agent he ended up dealing with. The man had been his main contact with the agency for years when asked to handle a mission for them. So few knew his name and what his night job was, and even fewer still got permission to call him by his first name while knowing that secret. Alex had been very careful in keeping his identity discreet when under his hood.

“You know Phil, one day I will get you to call me Alex or even Xander one day. Its a personal mission for me.” Alex gave his most dangerous smile that made even demons nervous.

SHIELD agent Phil Coulson smiled indulgently at his almost friend as both headed for the exit. Phil had their cars waiting to take them both away from the airport as standard procedure for them. Alex stared at the super agent who was being deliberately obtuse.

One of Phil’s earliest cases for SHIELD had been to recruit Alexander Castle to work with SHIELD. They had known about Alex since they had a constant monitor on the Punisher and his activities incase the man crossed a line too far. When Alex moved himself into the war against the supernatural and made some interesting acquaintances, SHIELD saw a unique opportunity.

Nick Fury, the Commander of SHIELD, had attempted to recruit Alex with blackmail and coercion to help them bypass the Watcher’s Council. The one eyed man personally believed the Council’s time was over as guardians for the world. Plus the man had learned just how corrupt the leadership of the group actually was. Fury preferred to have a more agreeable intermediary to liaise with the Slayer for them.

At least that had been the plan in the beginning. Alex didn’t work well with others except with an assorted few. The truth was the super secret agent was nervous around the talented young man and kept Alex from ever stepping foot on SHIELD’s Helicarrier. Alex had managed to keep his secret activities hidden till he required their aide in a certain matter. That had not sat well with a man that prided himself in knowing everything about everyone.

Phil turned towards his companion before they went for their own cars. “Before you go, know that I placed a birthday present for Natalie with your payment inside the briefcase.”

Alex’s face lite up at hearing his daughter’s name, acting very much as the proud father. He was glad he got back early as his daughter’s fifth birthday was in two days and planned to be home for it.

“Not gonna be able to make the party Phil? She’ll be disappointed if her Unca Phil doesn’t show.” Alex teased with a shark worthy grin.

He had been trying to introduce Phil to his family for months. Alex was very curious to see how Phil could handle meeting his Slayer wife. The dark eyed assassin was sure it would turn out to be hilarious for himself at least.

“Goodnight Doctor Castle.” Phil called out ignoring the man’s goading. The Agent quickly disappeared into the black sedan, leaving a frowning Alex as it drove off..

“Give a guy doctorate and some people will never let you forget it.” He hated the honorific involved in his civilian profession.

While Alex was a killer by trade, he worked as a pediatric doctor when he could to help balance his life. Treating and healing children was just as fulfilling to him as killing the demon and human scum of the underworld. He knew better now not to fill out the answers to some test Willow asked him to take.

However, before he could depart himself in his beautiful custom built BMW. Alex slipped into his habit of glancing around at his surroundings looking for any sign of threats with a special ability of his. A genetic talent referred to as Eagle Vision kicked in giving him perfect clarity around him. His focus zoomed in on a couple leaving the airport with a vampire silently approaching from behind.

With naught a sound, Alex glided up behind the vampire and a blade jutted out from his wrist with a slight flick of his hand. Blessed metal pierced the unanimated heart of the vampire causing a poof of dust for his efforts. Alex watched on in silence as he gently brushed some dust off his suit, the couple continued unaware of the previous danger they had just been in.

Alex returned to his vehicle with a smile to finally return home.


Alex arrived to a quiet manor in beautiful Venice that had been his home since before he got married. His wife’s eyes had been huge when he brought her there after their honeymoon. She was taken in by the beauty of the city, though he was positive that being close to a fashion capital of the world also helped in causing her to love their home. The tasteful interior decorating was easily lost on her.

With practiced skill, Alex entered his home but almost ungracefully tripped right away. Alex shook with head with annoyance when he nearly tripped over his wife’s sword she had leaning in the foyer. Picking up the object that would have sent him crashing into the floor, Alex almost missed another object in the area that sent him a bit of distress.

His four year old daughter’s jacket was in the entrance closet. What really caught his eyes was the three slash marks from claws gave him a bit of worry. He knew of his wife’s habit of taking their daughter patrolling with her for some mother daughter time. Normally his wife would only do it when someone was with her providing backup. Alex tried to calm down knowing the love of his life would have called him had their daughter been hurt bad.

After a quick trip to the basement where he and his wife kept their armory, Alex hurried to his daughter’s room where he found his precious little girl sleeping peacefully in her bed. A quick look with his enhanced vision showed she had not a scratch on her. Like himself and her mother, she was more durable than a normal human. In his case it was genetics, in his wife’s it was a mystical condition.

Content that his daughter was unharmed Alex kissed her head. “Daddy’s home princess. I will see you when you wake.”

A quick check in his bedroom revealed his wife hidden, curled up in their bed tangled in blankets and pillows. Smiling at the adorable sight of the woman he loved looking so innocent, Alex left his wife to sleep and headed to his office at the manor.

Alex disdainfully started up his computer. He was a simple man and a computer was more complex than he felt he should deal with. It was necessary however for his work as a doctor and to keep in contact with others. Looking at the used device, Alex thought on the latest attempts by some of his friends to upgrade the thing for him to something faster and newer.

The infernal machine as a certain watcher he knew called it, contained his training program he had been working on for his children to use in case something happened to him. Alex knew his descendants had very high chances of having all of his special abilities. Due to his medical background and extensive studying, Alex learned much about himself and the differences of his body from a regular human.

Glancing through the codex of information he gained in life and from an artifact Alex found years ago, he felt something was missing. Then he realized what it was, an opening message. With a sigh, Alex started the computer’s camera to start recording as he opened a magically and electronically locked safe. Inside housed the most dangerous and technologically advanced relic Alex had ever seen..

“My name is Alexander Castle and I’m an assassin. I was not born this way but have been ever since I came across this artifact when I was thirteen years old after running away from home.”

Alex glanced at the powerful gold item as his mind drifted back to the day he and a special destiny collided. It had started after running away from an abusive father and neglectful mother. He left all he knew and two special friends behind that fateful day. Alex had made it as far as Los Angeles when something hit him in the back of the head. When his hand first grasped the ancient artifact, he was shown the life of the one who handled it before him.

Alex learned about a man named Desmond Miles and the events of humanity in an alternate dimension. In his final moments Desmond had used the device to send a part of himself away and survive an action he knew that would cause his death. Originally it was supposed to go to another assassin to help stop the being known as Juno, a devious and malevolent being from a race predating mankind from taking over. But the search specifications were a broad set and wasn’t limited to a certain dimension which brought the device to Alex.

While being bombarded with memories and knowledge from another dimension, Alex hadn’t noticed at the time his body being changed. His genetics had been changed into a hybrid template. A mix between human and the ones known as the first civilization from an alternate earth. It made his reflexes and mind faster and improved his physical strength among other gifts from Desmond’s bloodline.

Memories involving the artifact from others who handled the apple flashed through his mind. A hood obscuring their faces as they stood amongst their enemies. Glimpses of assassins silently killing their unsuspecting targets before disappearing without a trace. Other flashes showed them standing on battlefields with hidden blades extending from their vambraces. The blades cutting a bloody swath through the ranks leaving a circle of dying and dead men around them.

The memories proved to Alex that he was the first of a new race. The Templars and the Assassin’s from the alternate earth accomplished feats unsurpassed by ordinary people. They had been altered in history by the first civilization just as Alex had been.

Thoughts then drifted to his own memories. A good man found Alex after he ran away from home and found the apple. He took the skills Alex gained from the apple and further trained and improved upon them with additional knowledge of modern weapons. His adopted father Frank Castle, better known as ‘The Punisher’, had introduced Alex fully into the hidden nightlife around the world. Further training by an honorary uncle and hard ass honorary older brother, Alex took the legacy he found and made it his own


Los Angeles, California ~ Year 1996.

It was after dark when Alex strode into the abandoned warehouse where he knew a certain pair of vampire hunters were hanging out. He could hear the muffled thumps of his honorary uncle trying to stealthily move to sneak up on him. The young man could only smile as he disappeared around a corner, intending to reverse the trap the aged vampire hunter was intending to spring. To his Uncle it was survival training and to make Alex more humble, to the young killer it was simply a game to amuse himself. Only a certain vampire hybrid has ever beaten Alex in a game of stealth.

Abraham Whistler snuck up on where he last saw the little punk that loved to make his life difficult and couldn’t listen worth a damn. He was positive he’d finally show the little shit who was the better hunter once and for soon as he could find Alex.

A chuckle sounded from above Whistler when he reached a dead end in the rows of junk in the old warehouse. The aged man cursed up a storm knowing the kid he referred to as a nephew only in the privacy in his mind had him dead to rights.

“Your dead Unc.” Alex fell from the shadows above and landing silently. It left the old man envious of his youth and skill for a brief moment before pissing him off even more.

“Shut your trap you little shit.” Whistler stomped his way back to his workshop with his lame leg leaving an amused Alex following behind him. “What the hell you doing here anyway. Last I checked your dad was somewhere in Europe right now if the gossip is anything to go by.”

Alex nodded absently as he went over to a workbench and hopped up on it for a seat. Through practice and experience he ignored the old man’s glare at disrespecting the man’s work space.

While his adopted father was in Europe, the feared Punisher decided to let his son and protege stay behind and find his own path now that he felt Alex was ready. He had been left with strict orders not to blow up anything bigger than a building and to try and have fun. The words that he was to try and find some kids his own age and relax was left unsaid between the two. One of Frank Castle’s biggest regrets is not keeping Alex from growing up too fast..

“He didn’t need any help for his next targets and decided to let me spread my own wings finally. Also since you and Blade been working in this city for a while I thought about checking out the local scene.” Alex’s eyes spotted a map on the wall by Whistler. “Hey Unc, you know that vampire club on 13th Avenue?”

Whistler froze recognizing the tone right away. It usually led to him being more pissed off. “What about it kid?”

“You can cross it off the map. I saw some vamps enter it before i got here and took care of it. Vamps were ash and the place burned to the ground. I even had marshmallows to roast.” Alex’s lips quirked up in a smile. Blade and Whistler hated it when someone else played in their sandbox.

Whistler glanced at the map and then back at the smart ass currently trying to get under his skin. He had planned to send Blade to the club after he got back from investigating the local blood banks for Vampire influence. Seeing the self satisfied look on Alex’s face he could only grumble and crossed the place off the map.

Alex slid the sleeves of his jacket up revealing the bracers that housed his precious hidden blades. They were his weapons of choice once he got used to using them in a close quarter fights. They were his ace in the hole on unsuspecting enemies that got too close for bullets or where stealth was key.

Using the knowledge from the artifact, he had forged the blades to be as strong as titanium. To aid in hunting demons, the metal had been given the same properties of silver along with being blessed by a preacher. Alex was thankful they didn’t cause metal detectors to go off when he went through airports.

When he finished his inspection, Alex picked up a tool off the workbench he was sitting on and got to work. He found it therapeutic to tinker with them to make sure they were in perfect working order. A hobby he picked up from Whistler truth be told.

Whistler looked at the weapons on Alex’s wrists and knew they weren’t the only weapons the lad had on him. He also knew the young man kept a silenced glock with explosive blessed silver rounds and a uniquely designed tomahawk hidden inside his jacket. Alex’s clothing also was as unique as some of his weapons. The clothing he wore had an expensive and unique nanoweave carbon fiber in the fabric making it tear resistant from blades. All of Alex’s jackets also had a hood hidden inside that was easy to pull out and wear to obscure his face when needed.

“So anything else going on in the city you could fill me in on? Alex asked as Whistler got back to work on making a new weapon Blade could use.

After a moment of thought he recalled something he could have the kid check into instead of sending Blade. While the Daywalker was good at getting the job done and kill Vampires, he was shit at dealing with regular people. That job usually fell to Whistler and he didn’t like doing it anymore than Blade did.

“There was a fire at a local high school a month or so back. A girl claimed she set it on fire due to vampires.” Whistler looked annoyed at Alex’s look of amused disbelief when Whistler showed him the article and saw how petite the girl was.

“She looks a hundred pounds soaking wet,” Alex replied in amusement but was staring at the cute girl in the picture until Whistler whipped the article away in disgust.

“Ever heard of the story of the Slayer?” The old man went back to tinkering at the other workbench.

“Yeah, one girl in all the world to fight the things that go bump in the night. I always imagine a girl like that would be like a female Blade...then I usually look for a place to vomit and bleach my brain.”

Whistler snorted. “Well the legend is real. Met a couple before years ago, though their stick up the ass watchers keep them on tight leashes.”

“And you think this,” Alex looked at the article again and his eyes widen in disbelief at some parent actually naming their child Buffy. “This Buffy is the Vampire Slayer?”

“Maybe. Since Blade is busy and likely to stand out like a vampire caught on fire I want you to investigate this. If she is the Slayer I want to keep tabs on her as Slayers are trouble magnets to the darker side of things.”

Alex hopped off the workbench and was thinking as he gave his weapons a quick inspection. “Sure why not. How hard can a cheerleader be anyways?”

Whistler snorted and smirked in amusement knowing the young man would be eating his words.

End Chapter

Author’s Note: The identity of Xander’s wife will not be revealed till a later time. One reason is I feel it's unnecessary yet and will ruin the mystery. The second reason is that I’m undecided on two women to take that spot. Only hint is its not Cordelia for certain personal reasons.
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