Disclaimer: I do not own either the Avengers or Undertale.

The Sansational Skeleton

Chapter 1: Not A Mettaton of Fun

It was a beautiful day outside. Emphasis on the was. Birds were singing not too long ago. The flowers that were in the midst of blooming were trampled upon. Sans ducked as a stray blade flew towards him. If he had any hair, he would have joked that it was a close shave. On days like these, Sans was usually at home by now.

Screaming humans ran past the short skeleton, fleeing the danger that pursued them. A giant robot was slowly approaching. Sans wished that it was just a giant robot. The addition of the many whirring and firing blades made it a lot more deadly. It would also make it look utterly ridiculous if it were not for the situation he was in.

Another wave of blades were shot at the humans. Once again, a wave of bones rose to stop them. If he was not there... Sans shuddered to think about what would have happened by now. The robot was slow, but had great fire power.

Almost all of the humans had evacuated the area by now. There were a couple of stragglers, however. Sans made sure to keep an eye socket on them as they fled, just in case. Thankfully, nothing happened, and they were past him after another minute.

Now, it was just Sans and the robot, disregarding the police barricade that had started cropping up in the past few minutes. If Sans decided to get serious, he was sure he could handle the robot on his own. He considered it briefly, but ultimately decided against it. It would do no good to show the amount of power that he had to the police... or to that helicopter that he saw flying overhead. When people saw something powerful, they feared it.

Sans focused on keeping the robot occupied for the next couple of minutes. He was sure that the barricade would not stop the robot, and would just be smooshed by one step. It was not hard to keep the robot's attention. Sans suspected that there was a human inside the thing, as a robot would not be so easily aggroed. A dodge here, a bone attack there, and the robot was furious.

During these last couple of minutes, Sans had noticed a familiar flash of blue arrive to the scene. Obviously, the flash of blue had noticed him as well, if the humans holding her back was any indication. Clearly Undyne did not want Sans out there, fighting all by himself.

Undyne did not have to worry for long. Soon enough, multiple figures joined the party. Sans sighed in relief. The Avengers had arrived. They could take it from here.

The Avenger Sans recognized as Hawkeye seconded his thought. "We've got this! Go!"

Not needing to be told twice, Sans dodged his way towards where he had spotted his friend earlier, occasionally summoning a bone or two to help deflect the blades targeting him. Once he was next to the barricade, a scaly blue hand latched onto his hood and pulled him up and over. If there was one thing Undyne had over him, it was height.

Sans knew that he wouldn't be released for awhile. When Undyne was angry with him, she often picked him up like this and yelled at him. And when Undyne was concerned... her reaction was worryingly close to anger a lot of the time.

Undyne just looked at him for a moment, eye roving over him checking for damage. When she found none, her posture relaxed slightly. Even so, she still managed to look menacing. Her eyepatch and ever perpetual scowl tended to have that effect.

If it was not for the fact that Undyne was a part of the police force and his own unworried smile, Sans doubted that Undyne's comrades would have let her hold him for this long. Perhaps she felt this way as well, and so started yelling out her piece, "Sans! What were you thinking?! You only have 1 Hp, Punk! One hit and you would be dust... DO YOU KNOW WHAT THAT WOULD DO TO PAPYRUS?!"

Undyne's fellow officers paled at her words. Most monsters could take more damage than humans could, not the other way around.

Undyne gently lowered Sans onto the hood of her police car and continued on, voice much softer than before, "Still... you did some good out there. I can't really be pissed at you when you did what was right..." Undyne nodded towards a couple of children, the stragglers that Sans had noticed before. He was relieved to see that an officer was taking care of them. Events like this were not easy to get over.

"i'll keep that in mind, undyne." Sans winked at her and added, pointing at the giant robot, "i didn't have a mettaton of fun anyways. dodging just takes too much energy."

Undyne just sighed at her friend's pun. At least she knew he was alright emotionally if he was punning.

Attention still turned towards the robot, the two saw as it buckled under its own weight. Sans burst out laughing as he noticed the cause. "the robot used to be big and scary, but then it took an arrow to the knee!" Sans had definitely looked at way too many memes in his spare time.

One of the police officers laughed with him, while another just shook his head and noted that the meme was outdated. Still, there was a slight smile on his face regardless.

Sparks shot up from the robot as it malfunctioned. It was not programmed to deal with a lack of leg movement. How shocking, Sans absentmindedly thought. Someone obviously spent a lot of money building that robot, so couldn't they have done a better job programming it? Then again, they're not too smart in the first place if they've gone the route of being a supervillain. To Sans, being a supervillain just sounded like a big waste of money and lots of jail time.

Suddenly, the head of the robot opened up and a chair shot up into the sky, a parachute attached to its arms. If he squinted, Sans could make out a human riding the chair. The villain tried to get away by activating a fan on the back of the chair. For a moment, it looked like it would work... and then the fan sputtered and died, burnt by a pursuing laser beam. The villain looked frantic as they fell towards the ground, the parachute keeping them safe, but not free.

After a minute of tense waiting, the villain's descent was over. Soon enough, the mastermind behind this whole disaster was sitting in cuffs, being read his rights by the police.

Undyne stayed with Sans at her car, eye narrowing as she saw the Avengers approaching them. She respected them and appreciated all their hard effort, but she knew that Sans did not like extra attention. At least the Hulk had changed back to his human form. It would be an accident waiting to happen to have him still hulked out.

Surprisingly, Sans greeted them first, "eyy, nice one hawkeye. that robot used to be an adventurer like you..." Undyne was not surprised anymore. Sans liked his jokes too much.

Ironman lifted his face plate up and finished the meme, mouth twitching into a smile, "Until he took an arrow to the knee!"

Somehow, Sans knew that he and Ironman would get along just great.

"Why do you think I keep aiming for the knees?" Hawkeye winked, implying that he did it on purpose.

Sans was starting to like these guys.

Black Widow replied in her usual logical tone, "We're supposed to catch the villains, not kill them. An arrow in the knee only wounds and is thus suited to the purpose."

Just going by the tone of her voice, Sans would have thought she was serious... but her lips were slightly upturned. It looked like these guys knew how to have a good time.

A few feet away, Sans could hear an ongoing conversation. It appeared that Thor and Captain America were questioning the man behind the hulk about the meme.

Sans was about to butt into their conversation with some choice puns, but was soon distracted by his name being yelled.

"SANS!" Papyrus shouted, running towards him. "ARE YOU OK?" For the second time that day, Sans was picked up. Except for this time, it was a princess carry. It always amused Sans that his brother tended to carry him around when he was worried about him. At times though, it could be a little stifling, but it could also be a chance for a nice nap.

"sup paps." Sans winked, "you could say i'm just holding out fine, bro."

Sans laughed as the taller skeleton screeched at his pun. It was always very punny to see Papyrus' reactions to his jokes. Although it did tend to hurt his non-existent ears when his brother yelled so close to him.

Another, softer, voice joined the conversation, "Papyrus, dear, perhaps you should put your brother down. Tibia honest with you, I do think that he would rather be on his own feet in front of others."

While Papyrus complied with her wishes, Sans waved hello to Toriel. "you've goat to be kidding me, tori. when did you goat here?"

The big, fluffy goat monster gestured to a red sports car, where her ex-husband was just exiting. "Your brother drove us. You had us worried when you showed up on the television."

"and frisk? where's the kiddo?" Sans pondered.

"FRISK IS STAYING WITH DR. ALPHYS." Papyrus volunteered.

"ah that's good-"

An explosion rocked the area, and everything went to hell.

Pieces of the robot were scattered up into the air. The ground where it was had a giant scorch mark on it and a miniature mountain of rubble already laid there. Screaming stained the air, the cries of trapped police officers emanating from the epicenter. The villain was running away, a remote casually thrown behind him. Sans just knew that the robot's design was suspicious!

Thankfully, the monsters and Avengers were quick to react to the change in situation.

Magic filled the air as each individual monster did their thing. Toriel ran towards the injured police officers, intending to heal them. Asgore followed right behind her, protecting her with his summoned trident. Papyrus summoned bones to protect against the rain of rubble, doing his best to enclose the police officers under cover. Sans left eye flared up blue, and he considered which pieces of flying rubble would be the most troublesome and encased them with blue magic, intending to buy time for everyone to get away. Undyne held the fort, protecting both Sans and Papyrus by deflecting any rubble heading their way.

The Avengers were not outclassed. Ironman blasted large pieces of rubble with his lasers, carefully flying towards his next target. Hawkeye likewise shot at the rubble with trick arrows, trapping some rubble up in nets against buildings, and blasting apart others. Captain America focused on protecting, using his large shield... as a shield to shield whoever needed it at any moment. Thor flew around, using his giant hammer like a baseball bat against the rubble. He was careful, however, so that the new trajectory of the rubble was not troublesome. The Hulk was catching pieces of rubble and gently setting them down on the ground. Black Widow was chasing after the villain.

After a few minutes of this fiasco, all the rubble was taken care of. However, there were still injured policemen to tend to. Overall, there were a few dents in the armor of the Avengers, but there were no more serious injuries than they started with.

The crisis was past.