Undertale meets Shield

Arrest

Sans was suddenly pushed to the ground by Undyne. "The heck man! Why did you attack Frisk!" Undyne yelled, every monster surrounding them. Sans didn't reply as he glared at the ground.

"Undyne? What is the meaning of this?" Asgore asked as Sans balled his fists. "Brother? What is the matter?" Papyrus asked as Sans squeezed his eyes shut.

"What's the matter is Sans attacked Frisk!" Undyne yelled as she pointed at Sans, Papyrus didn't care at the moment and walked closer to his brother. Gasps and whispering were heard among the crowd of monsters. "Sans, is this true." Toriel asked as Papyrus kneeled down to Sans in an attempt to help him. "It's okay." Frisk said as they grabbed Undyne's hand. "Mercy." They said, Undyne looked at Frisk and then Sans.

"No." She said and yanked her hand out of Frisk grasp and held up her hand to make her spear. "He tried to hurt you and he has to pay." She said, Everything suddenly became slow as Undyne tried to hit Sans with her spear. Toriel, Asgore and Papyrus tried to stop her, until a net was shot at Undyne which then caused her to fall onto her back.

"Go, go, go, go!" Soldiers yelled as they kicked down the wooden gate and aimed their guns at monsters. Sans groaned as he sat up and looked ahead to see he was staring at Nick Fury.

"What is the meaning of this?" Toriel yelled as Nick walked through the crowd. "Monsters of this mountain, you are under arrest." Nick said, Sans stood up as some of the guards held up cuffs and started cuffing some monsters.

"What for? We haven't done anything against your laws." Sans asked, Nick grabbed a tablet from his side to show a picture of Sans and Frisk in the tent a moment ago. "Apparently you have. Let's go do this." Fury said, A guard came up to Papyrus and cuffed him.

"Ow! Sans! What's going on!" Papyrus asked. "No, no, no, no!" Sans said and was about to run to his brother until a guard grabbed his arms. "You can't do this!" He yelled.

"Nick!" Nat yelled as the avengers suddenly ran up the mountain. "Stop! There's something wrong going on!" Nat pleaded."Rachel?" Toriel asked, Nat looked at Toriel. "Y-you were lying to us?" She asked, Nat tightened her lips. "But we, we didn't do anything wrong." She said and started to be taken away.

"No! You have to stop!" Sans yelled as he saw all his friends being taken away. "Nick, we saw this other monster and they tried to explain that if we attack, something bad will happen." Steve said, Frisk walked over to Sans.

"Sans? Are you okay?" They asked as Sans glared at the ground. He suddenly started to glitch. "What do you mean by something bad will happen?" Nick asked, they tried to explain more and more until Banner noticed Sans glitching.

"Sans?" Frisk asked and touched his back. They yelped and pulled away their hand as it started to glitch. "Uh, guys." Banner said, they turned and saw Sans and Frisk glitching. "Leave them, ALONE!" Sans yelled as his jacket became black and his once blue eye became red. Red attacks sprouted everywhere. Sans kicked the guard off and punched the ground, creating another wave of red attacks. He then started glitching even more and his eyes became purple.

"Don't shoot! Don't shoot!" Frisk pleaded as their sweater suddenly became red and black with a bandaid on their cheek. Sans turned his head to the sky. "It's a beautiful day outside, birds are singing, flowers are blooming. On days like these, people like you, should be burning in hell." He said and several attacks along with his soul and blasters appeared. "Take cover!" Many of the men yelled Banner's skin soon turned green and he became the hulk. Sans turned his head to the hulk.

"So that's why you were on the battlefield." He said and raised his hand, the hulks soul then became blue as he was raised up into the air. "One monkey fell off and bumped his head." He sang as he dropped hulk and laughed a bit.

"Jarvis! How do we stop this guy!" Tony yelled as the avengers took cover. "I'm getting a giant read of magic in his soul. Perhaps that is his source of power." Jarvis said, Clint nodded and aimed his bow while Frisk ushered the other monsters to take cover. "I can't get a clean shot!" Clint yelled, suddenly all the attacks and Sans himself started glitching.

"NO!" Sans yelled as he grabbed his head. He started glitching and his form turned into one where he was wearing armor. Another was on where black bird wings sprouted in the sky. Clint took a deep breath and shot his arrow.

"NO!" All of Sans' friends yelled as the arrow landed right in the center of Sans soul. Sans stopped glitching as he looked down at his soul. Giant -9 appeared around Sans as he fell to his knees.

"Let me go! I have to help my brother!" Papyrus yelled as he struggled. He fell to his knees and started crying. "You KILLED HIM!" He yelled, a sudden moment of silence washed over everyone. Sans looked at his hands and laughed while smiling.

"Guess cupid's arrow did it's job a little too well." He said and laughed for a moment as he started to turn to dust. Then, the black sludge from before appeared. Sans looked at it as it took the shape of a monster. Sans went wide eyed as the monster looked at his soul. The monster grabbed the arrow and pulled it out.

"What are you doing!" Undyne yelled, the monster looked at her with annoyance before turning back to Sans and placed his hand on Sans's head. The hole in the center turned green. "What is he doing?" Nick asked as Toriel stood next to him.

"The monster is, healing Sans?" She asked, once the green glow disappeared, Sans fell to his side as a giant +1 appeared above Sans. The monster then turned to the avengers. He looked at Clint who seemed worried. "I hope this helps understand who I am." The monster said and raised the arrow into the air before crushing it. He then disappeared before anyone could do anything.