Thanks to: RickW22, HolyKnight, YoraththeWolf, Ckk, Direwraith, Xon, Quatoria23, Demented Mite, Davelister, Tammin, Blacksands, Da5id, Xman, Bolo, Inva, HolyKnight5, and Dogbertcarroll. Even though not all your reviews were posted by because of their update problem, I received them all so thanks.

To everyone interested, I have received suggestions form a couple of people about crossing this with SG-1 as well. Send me a review and tell me whether I should do it in this story or hold off for a sequel.

HolyKnight: We may or may not see some of the stuff you suggested, I haven't decided yet. You'll just have to wait and see.

YoraththeWolf: You are right, Warren was the Elite. Thanks again for the long review.

Direwraithe: Read on and find out.

Xon: John, Spartan 117 actually. I just finished reading the books.

Davelister: The Arbiter will eventually show up, that's all I will say.

HolyKnight5: Well, not quite. All humans have a neural interface and Spartans are no exception, but I think they actually look at a HUD on the faceplate of the helmet.

Some quick information. Here are the Covenant species names because I have used a couple in this chapter.

Unggoy: Grunt
Kig-yar: Jackal
Lekgolo: Hunter
Sangheili: Elite
Jiralhanae: Brute
Yan'me: Bugger

Anyways I think that's all so on with the story!

Chapter 4

Xander, Buffy and Giles sat in the library, trying to work out the logistics of patrol routines. Xander sighed and leaned back in his chair as Buffy continued to argue.

"If Xander wants to patrol every night he should wear the armour." Buffy insisted.

"Buffy I used to patrol with you all the time before I became a Spartan." Xander said. "Why are you suddenly all freaked out about my safety?"

Buffy bit her lip. "Xander, when you used to come patrolling with me you had the good sense to stay back. Now you might get yourself into a situation where you bite off more than you can chew, and then I won't be able to help you. At least if you wear the armour you won't get bitten."

Xander's temper flared. "Buffy, I'm not a little kid that you have to protect. I've survived this long without any special abilities, you think the first thing I'm going to do now that I have some is go out and get killed?"

"But-"

"Xander, perhaps it would be better to air on the air on the side of caution, at least for now." Giles said. "For now wear the armour and try to stay away from any public areas."

"Giles I can take care of a couple of vampires without it." Xander argued. "I've been training with Buffy for over a week now, I can handle myself almost as well as she can."

"Xander, to be honest I've been holding back a little." Buffy said gently. "You're good, and you're getting better, but you're not as good as me, at least not without the armour."

Xander slumped. "Fine, I'll wear it for patrol at least for now. But Cortana warned be that I can only turn the suit on and off so many times before I need a zapper."

"A zapper?" Buffy asked quizzically.

"It recharges the shields." Xander explained.

"Oh don't worry about that." Said a voice from the computer on the library table. Cortana smirked. "I'm working on it."

----------

Xander twirled the stake in with surprising agility in his armoured hand. He leaned against a tree while Buffy lounged on a tombstone, waiting for a new vampire to rise. It was Xander's first outing with Buffy after his transformation, and he was filled with a surprising confidence that he supposed came from the Master Chief side of him. It wasn't so much that he was no longer afraid, more that the fear took a back seat to completing his objective now.

Buffy looked towards the grave as a hand emerged from the dirt. "You want this one?" She asked.

Xander shrugged inside the armour, translating into a barely noticeable movement to anyone watching. "Sure." He replied nonchalantly. Xander waited for the vampire to completely emerge and dust himself off before stepping out of the shadow of the tree.

The vampire watched him with an expression not so much of fear, but of fascination. Wearing the metallic green armour Xander looked very big, and with the helmet on no part of his face was visible. Despite the combined weight of Xander and the MJOLNIR armour coming to a little under 900 pounds, Xander moved with a fluidity that was almost inhuman. Xander let the vampire make the first move, a haymaker punch that he easily blocked. Then instead of letting the vamps arm go, he grabbed it and jammed his other forearm in the vampires elbow, shattering it.

The vampire yelped in pain, and Xander took the opportunity to step in and smash the vampire's knee with a downward kick. Then he quickly unclipped his stake from his belt and stabbed the vampire before it hit the ground. He turned and dusted his hands while he re-clipped the stake, which he had attached a small clip to, onto his belt. "Told you I didn't need the armour." Xander said matter of factly.

Buffy was more surprised by the brutality of his attack than anything else. Had the vampire been human instead, the only two attacks Xander threw would have left him crippled for life. However before she could respond a large, snarling demon with four huge fangs like a sabre-toothed tiger and a grotesque, green slimy body came around the side of a mausoleum.

Xander stared at the hideous creature. "You know what?" He commented, "Never mind. I'm glad I wore the armour."

Buffy stared at the approaching demon with an expression of disgust. "Eww, I didn't even wear gloves." She said, looking at the skin that was completely covered in a layer of slime. "Can you take care of this?" She asked.

"Oh sure, pass your job off to me just cuz I'm wearing an airtight suit." Xander said, moving to engage the demon. "Thanks a lot." Xander moved in and threw a punch that acted like a clothesline, knocking the demon to the ground.

However, almost as fast he was back on his feet and lashed out with a talon-like hand, striking Xander in the midsection. Xander was surprised to see that the blow had dropped his shield strength by half. However, Xander moved quickly, throwing a lightning fast punch to the creature's neck designed to choke it. The creature staggered back and roared with pain, but moved forward again letting Xander know that the attack had failed in its' primary purpose. Xander stepped in and threw another punch that impacted the demon in the jaw. Its head snapped back, sending a small spray of slime out. While the demon was stunned Xander unsheathed the hunting knife he had brought along as well and twirled it once, then jammed it between the creatures eyes right to where he hoped its' brain was. The demon immediately stopped moving then dropped to the ground.

"Wow." Buffy appraised. "Nice job."

"Thanks." Xander said, looking at the slime that now coated his shields. "Yuck. Let's go home so I can clean up." Xander grabbed the knife from the demon's head, the re-sheathed it and dragged the demon's body to the now empty grave of the fledgling vampire. He pushed it through the hole left by the vamp and turned to head back to Buffy.

"Xan come with me all the time now." She said. "I hate having to clean up some of the demons, you have no idea how many are slimy like that." Buffy gave Xander a winning smile.

"Oh I see how it is." Xander grumbled jokingly. "Well I'll clean now, on the condition that you clean up if my enemies show up."

"Sounds fair." Buffy said, causing Xander to laugh. "What?" She asked.

"Covenant bad guys splatter a lot more than demons." Xander said, walking away.

"Ahh!" Buffy shouted. "No deal! Xander! Wait up!"

----------

"Cortana, why am I walking around in an industrial district?" Xander asked. "Someone could see me."

"Xander it's 11 at night." Cortana replied. "There is no one here, now just keep going, it's right around the next corner."

"What is?" Xander asked.

"A surprise, okay?" Cortana said. "Just keep your pants on, man you're impatient."

The two rounded the corner and all Xander could see was an abandoned looking warehouse. "Okay." He said, "Where to?"

"Go inside." Cortana said. "I have to leave for a minute, I'll be right back."

"Should I wait for you?" Xander asked.

"No I'll be back in just a second." Cortana replied. Xander felt the cool sensation of Cortana against the back of his brain vanish as she left the armour. Xander still wasn't sure how, maybe she had linked the communicators to the suit. He moved forward and opened the door, stepping into the darkened room. Immediately the lights came on, and Xander saw that what he had assumed was an abandoned warehouse looked a lot more like a robotics lab. There were robotic arms and welders and, much to Xander's surprise, a zapper in the middle of the room. What was even more surprising however, was a life-size hologram of Cortana lounging in a chair near the zapper.

"So," she asked smirking, "What do you think?"

"This is amazing!" Xander exclaimed as he took more of the room in. In one corner of the room there was a maintenance bay, another seemed to be a training area, and in one corner there appeared to be a weapons locker. "How can you possibly afford this?" Xander asked.

"Well technically, you did." Cortana replied, standing up and stretching her translucent, purple frame. "See, I kinda borrowed some money from your bank account."

"Last time I checked the balance of that account was not seven figures." Xander said suspiciously.

"More like eight, but either way very true." Cortana said. "Fortunately for us, there's this little thing called the stock market…"

"You made more enough money to afford all this playing the stocks?" Xander asked. "In a week?"

"Five days Shorty, you can't trade over the weekend." Cortana replied smugly.

"Isn't this, you know, illegal or stealing in some way?" Xander queried. "Like counting cards or something?"

"No there was nothing illegal about what I did." Cortana replied. "All kinds of people using trading programs to help them make money, I just work a lot faster than any of them."

Xander shrugged. "Okay then." He took of his helmet and set it down on a table beside him. "So how did you build this place? Aren't you, you know, non corporeal?"

Cortana slinked over to him with a sly look on her face, then reached up and to Xander's shock, touched his face lightly, then gave him a light smack on the cheek.

"Whoa!" Xander exclaimed. "How did you do that?"

"Solid holograph technology, courtesy of the computer systems on Halo." Cortana said. "The Forerunners really knew their stuff. Anyways, I had some of these robots build and set up the holographic emitters, then I did some of the set up and the robots did some of the set up. Let me give you the grand tour." She took Xander's hand and let him across the room to the maintenance area, which included the zapper. "Here's where we can take care of your armour. I've got a couple of spare parts already built, plus the zapper, some welding robots, and even a flash-cloning machine."

Xander recognized the term immediately. Flash-cloning machines were used to make fast clones of organs that could be implanted in battlefield scenarios. "Let's hope we never need that." Xander said gravely.

Cortana nodded. "Hear hear. I also have a small vat of hydrostatic gel in case your suit needs to vent some. And if you follow me over here we have a small weapons area."

Xander examined the barren area of the warehouse. The only visible objects were five small doors on the wall with buttons beside them. Xander moved to one of the buttons and pressed it, and the hatch on the wall beside it popped open. A tray emerged and on it was a battle rifle and a stockpile of ammunition. Xander pressed the button again and it slid away, and he moved on to the next one. This one contained two SMGs. The next held a shotgun, then a pair of magnums, and sitting on the last tray was a Jackhammer rocket launcher.

"You might want to save that one for special occasions." Cortana commented. "Of course since I had to build these with materials available here, they are a little heavier than the ones you might find in my time and pack a little less punch, but they should still work just fine. I set up a little shooting range if you want to try them out."

"Maybe a little later." Xander said, looking at one corner of the warehouse that contained a smaller building. "What's in there?" Xander asked. "Office?"

"Nope, your new room." Cortana replied. "After observing your home for a week, I decided it was time for you to leave. In fact, why haven't you before now?"

Xander winced at the question, and the memories it brought up. "Can we just move on?" He asked.

"Fine, be that way." Cortana replied. She opened the door to the room and Xander stepped through and gasped. Against one wall was a big screen TV, against another was a computer with a bar fridge beside it, and across the room was a very comfortable looking bed.

"Cortana, you didn't have to do this for me." Xander said appreciatively.

"Hey, it was no big deal." Cortana said. "Consider it my way of paying you back the $50 I borrowed from you to pay for all this. Besides, your dad was a jerk. And if he pushed you too far, you might have lost it and with your new strength done something you might regret later."

"Still, this is awesome." Xander persisted.

"Now, let's get you out of the armour and get it cleaned and maintained." Cortana ordered. "We need to keep it, and you in perfect shape, just in case."

---------

Over the next couple of weeks things seemed to cool down over the Hellmouth. Willow started dating a guy named Oz, who Xander immediately decided he liked. Xander continued to train with Buffy, but they decided to split their patrols, with Angel working alongside Buffy and Xander working with Cortana. Xander found a strange satisfaction in working alone, or at least without another physical teammate. It was how the Chief worked, either alone or with other Spartans, and it was how Xander seemed to be the most comfortable working as well. Not to mention that he didn't particularly like Angel.

Tonight, however, Xander and Buffy were patrolling together. It had been a slow week and both Buffy and Xander were bored and decided since there was a heavy fog it would be better to stick together. In fact, they were about to call it quits when a large red dot appeared on Xander's motion tracker. Xander peered through the fog and made out a large shape, perhaps eleven or twelve feet tall. There seemed to be spikes coming off its' back, and something about that put Xander on edge.

"Heads up, we've got a contact." Xander said. "Demon by the looks of it."

Buffy drew her short sword and Xander reached for his knife, then stopped. Something about this shape looked too familiar. "Cortana, is that what I think it is?" He asked.

"Afraid so, Xander." Cortana replied.

"Buffy, stay back." Xander said. "That isn't a demon, it's a Hunter."

Buffy, who had been briefed on Covenant baddies, stiffened. "The big one that's really strong and really hard to kill?"

"You got it." Xander said, drawing his pistols. "I'll take care of it, just stand back. Even a stray blast from that fuel rod cannon could cook you." Buffy nodded and back off to a further position. "If he gets past me, go for the exposed skin on his back." Xander ordered. "That's his weak spot."

Xander moved slowly and quietly toward the Hunter, who was looking around in a confused manner. Behind him was a trail of broken tombstones and large footprints. "He must have just gotten here." Cortana commented.

"Let's send him back." Xander replied, gripping the two pistols tightly. He moved out when the gigantic alien faced away, but made a little too much noise and the Hunter whirled around to face him, it's fuel rod cannon already charging.

Xander dove out of the way as a stream of green irradiated plasma blasted apart the ground he had occupied just a second before. Xander rolled up and brought both his pistols to bear, quickly squeezing off a couple of round that bounced harmlessly off the Hunter's massively thick shield. The Hunter, now ready and lowered to its' combat posture, charged at Xander clumsily. Xander waited until the Hunter was right in front of him, then coiled his legs and jumped, three meters up and over the Hunter. He landed on the ground and was about to fire when the Hunter flung his arm around behind him and swatted Xander, reducing his shields to almost nothing and sending him flying.

Xander landed on a tombstone, knocking it over. "You know, that's bad luck." Cortana commented.

Xander stood up quickly. "That's a new trick." He said, then turned and ran back towards the Hunter, getting too close for the Hunter to fire its' cannon. Once again, the Hunter swung at Xander and Xander dodged again, only this time instead of going over the alien, he sidestepped. Xander leveled the pistols and opened fire, emptying both clips into the Hunter's exposed side. The Hunter gave a roar of pain, then collapsed to the ground.

"Good job." Cortana said. "But you know, Hunters always work in pairs. I wonder if…"

"Xander!" Buffy shouted. "Look out!"

Xander turned in time to see the huge green blast right before it impacted him. Xander's shield immediately dropped to zero and the heat inside the suit rose dramatically. The suit automatically vented some of the steaming hydrostatic gel to try and compensate for the temperature change, but Xander still felt the heat begin to blister his forearms slightly. Xander shot forwards, moving as fast as he dared in the suit. He rapidly closed the distance between himself and the second Hunter before it could fire another shot.

"Xander, your shields haven't recharged yet." Cortana warned. "If he hits you you're roadkill."

Xander ignored the AI. He ran straight at the Hunter and leveled both his guns. He knew he had only a couple of bullets left per gun, and he had to make them count. As the Hunter reared to his full height and prepared to crush Xander, he aimed and fired, aiming not for the midsection but for the exposed skin of the neck. The magnums barked out twin flames, and Xander emptied the remainder of both clips into the Covenant behemoth. This Hunter didn't roar, it instead splattered orange luminescent blood across Xander's unshielded armour, then dropped to the ground.

"Oh gross!" Buffy said loudly.

Xander looked down at the huge corpse. "Damn, almost a month without any Covenant problems and now this!"

"Well our luck had to run out some time or another." Cortana said. "We should be thankful it was only two Hunters."

"Yeah but what if they had gotten loose in the town before we found them?" Xander pointed out. "We need to set up some kind of alert system in case this happens again. I can't imagine how much damage a few Elites could do to Sunnydale."

"Maybe Giles or Willow can help us set up some kind of magical alarm system." Buffy added.

"We should definitely talk to them about it." Xander said. He looked down at his stained armour. "Let's get rid of the Hunters then call it a night, I want to wash this stuff off before it starts to smell."

----------

Covenant Holy City High Charity

The Prophet Truth stared down at the bowing Jiralhanae before him. "You say you witnessed the disappearance of the Lekgolo pair, yes?" He asked.

"I did, your majesty." The Jiralhanae guard replied. "The Lekgolo pair were manning their station, when a vortex appeared to envelop them."

"A vortex?" Asked the Prophet of Regret. "Can you elaborate? Is this the work of infidels? Perhaps a new human weapon?"

"I do not know, your majesty." The guard replied. "It looks similar to a slipstream vortex, only it was a deep green. I do not believe it to be the work of the humans, nor the work of heretics. It was something else, perhaps something spiritual."

"Watch your tongue, Jiralhanae." Truth stated. "You are walking a fine line between truth and heresy." He leaned back in his chair. "Have the whole city searched. If the Lekgolo still remain here, we will find them. In the mean time, we have a more important matter to deal with."

The Jiralhanae left and Truth looked at Regret. "There is more here than it appears. Lekgolo pairs are too large to simply disappear."

"I agree." Regret replied. "We should divert some resources to exploring the matter. In the mean time I must join with my fleet, and you should tend to the trial of the fool commander at Halo. We must make an example for the public."

"It will be done." Truth replied gravely.

----------

Xander walked into the library the next day only to be met with concerned gazes from Giles and Willow.

"Xander!" Willow shouted, running from her seat and grabbing him. "Buffy told us all about what happened. Are you okay?"

Xander smiled. "No big deal Wills, just a little singed." He pulled back the sleeve on his long sleeve shirt to show that the skin underneath was red as though it had been sunburned. "I'll be fine."

"It was too much perhaps to hope that this would never happen." Giles said. "I am glad however, that you were in the area when those creatures appeared. From what Buffy and Cortana have told us they could have done quite a lot of damage."

"Yeah, did she ask you about setting up some kind of alarm system?" Xander asked. "Hopefully we'll have a while to work on this but we need to have something in place when this happens again."

"She did, and I have been researching the subject." Giles replied. "I believe we should be able to get something in place soon. In the mean time, we have another problem. It seems Spike has been rallying a gang in the past few weeks, and from what Buffy has discerned he is planning to go after her."

"Doesn't make a lot of sense." Xander said. "Spike doesn't seem like the type to send people after Buffy, I figured he'd want to do it himself."

Giles considered this. "Perhaps the thrashing Buffy gave him on Halloween has taught him a lesson?"

Xander snorted. "Yeah, that's it. Spike learned something."

"Maybe it's a distraction." Willow said. "Trying to keep her busy?"

"Could be." Xander said. "I wouldn't be too worried about it though. He still doesn't know that I'm a Spartan, so we have an ace in the hole. Whatever he's planning, we'll get him."

----------

Cortana was bored. She got bored pretty easily in fact. She was watching an episode of Red vs. Blue when something in a nearby data stream caught her eye. Someone was trying to hack into government security. Normally she wouldn't have cared at all, pathetic human hackers tried that kind of thing every day, and the reasonably respectably security (for it's time) government security did a good job of fending them off. However, whoever was doing this was using decoding sequences that were far ahead of their time. Far ahead, and in fact alien. Cortana immediately realized that the code being used was Covenant in origin, although mixed in with a healthy dose of human hacking techniques.

"What the hell is going on here?" Cortana asked of herself. She watched as the hacker broke through the myriad of firewalls and proceeded to download secret documents relating to plasma control and regulation. He also tried to relocate government funds into an account somewhere. "Oh, I don't think so." Cortana mused. Disguising herself as a government security program, she terminated the hacker's connection easily and stopped the transfer of funds. Cortana tried to search the location of the hacker, but his connection to the internet shut down before she found any useful information. "Huh." She said. "This is just to strange. Why would anyone with Covenant information need human technology relating to plasma?" Cortana decided she should probably tell this to Xander, then went back to watching cartoons.

----------

Warren cursed. The government had found him somehow before he got the money he needed, but at least he had the last of the information he needed to start building plasma weapons. 'In good time.' He though to himself. 'In good time.'

End chap 4

Hope you guys liked the chapter! Thanks again for reading and please leave a review!