All this stuff is owned by Disney. This is crossing over with a bit more than bh6 and frozen lol. There's a bunch of pairings in this fic.

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Hiro awoke to find Elsa sitting on the edge of his bed. "I was wondering why the room felt so cold." Her eyes widened, "I'm so sorry! I didn't mean..." Hiro just gave her a playful grin, "I was just kidding."

"Hans said you know that Tadashi might not be the way you remember him." "Yeah, we talked about it." Hiro clearly looked worried but... "Hans doesn't get it. I think, because of his family.. That messed him up real good." Elsa frowned, "Just be careful. Hans can be really dangerous if you let your guard down."

"And Tadashi? Do you think he really would..." "I don't know. But do you think you could reach him if that's the case?""Tadashi has never given up on me or Baymax or even that professor of his. I wouldn't be much of a brother if I gave up on him." Elsa hugged him, "Tadashi is just as lucky as I am." She pulled back, giving him a stern look, "Don't let him push you away, no matter what happens or what he might say." "He wouldn't hurt me..." "Not on purpose, no. But it's like Wasabi says- it's better to have one contingency too many than one too few" "Wasabi, huh?" Hiro smirked. "Increased heart rate, flushed cheeks..." Baymax began. Hiro smiled nervously at the robot, "Maybe you'd be safer checking up on Hans."

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/Unknown ship spotted by abandoned quarantine island,/Tadashi's expressionless voice echoed in the King's mind. "Shall I engage?"

/Observe for now. Describe the vessel./

/Approaching/

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"May I scan you?"

Hans glared at Baymax, "It's best you didn't. I hardly slept."

"Insomnia can be the result of..." the robot began. "Be quiet," Hans growled, studying the sky. A small figure began to come into view, his posture rigid and blue flames coming from his heels. "Get the others!"

Baymax ambled towards the stairs. Hans sighed in frustration and fear as he began to recognize the uniform of his brother's private guard.

Hans then heard Tadashi mockingly whisper in his ear, "Miss me?" He hadn't even heard him land. Hans turned to look at him, the feeling of horror growing before their eyes met. Tadashi's eyes were glassy and hollow.

"W-what happened to you?" Hans asked. Tadashi laughed, taking off his nutcracker-esque hat and revealing his slicked back hair, "You did. This silly little peasant would do anything to keep you alive and that's all I needed to override his will." Hans paled, recognizing his eldest brother's voice coming from his- his... He couldn't finish the thought, didn't deserve to... And then Hans heard Hiro gasp from behind him. Perhaps they all had, but Hans wanted Hiro to see this least of all.

"You're lying! Hans said..." Hiro's voice trailed off. "Hans says a lot of things, doesn't he? I'm sure Elsa has told you plenty about what he's really like."

"At his worst, he's never done something like this," Elsa wasted no time and froze Tadashi solid. "It's only a matter of time before he melts it," Abby muttered. "So I'll just keep freezing him. Grand Pabby, please..." The elder troll nodded and approached the iceberg. Tadashi smirked and melted the ice around his head, stopping at the neck. "Don't you have couples to fix up or children to steal?" he smiled nastily. Pabby pretended not to hear as he studied Tadashi's eyes.

"Some sort of magic potion derived from the Goblin mirror," he said sadly. "My magic is no match for it."

"What is the goblin mirror?" Elsa asked as she began refreezing Tadashi. "It's freedom. Being able to see things as they really are," he smirked at her. She shuddered. "No! It means you're not yourself," Grand Pabby replied.

"Wasn't Gerta able to melt it in the story?" Hiro asked in a small voice. "Please, Dashi. Fight it, I know you can."

"Are all little brothers this weak and troublesome?" The King of the Southern Isles' voice boomed from Tadashi.

"I only see someone sending a puppet to fight because he's too weak to fight on his own," Grand Pabby said.

"And I see a troll meddling in human affairs above and beyond the limits allowed by his own council," Tadashi hissed.

Hiro stared him down, "Whoever you are, get out of my brother!"

"You didn't even look for the body, did you? If you had, I would have never gotten ahold of him. You gave up on your big brother!"

"Stop it!" Hans yelled as Hiro sobbed, his legs giving out. "It's contagious, apparently," Tadashi sneered.

Abby hugged Hiro, never so little or sad in the time she'd gotten to know him, "How could you?"

"Oh, Abigail. It must be a relief to know your father didn't trade my life for yours in the end, isn't it!"

Abby lunged at him but Wasabi held her back. "Don't you see, he's baiting us?"

Tadashi rolled his eyes and let out a huge burst of flames that released him and flickered towards Wasabi, "Oh do be quiet. It's embarrassing enough watching you hover over your ice monster girlfriend."

Elsa took a deep breath and grinned, "Ice monster, you say?" With a few waves of her hand, the entire ocean of the Southern Isles flew upward and froze into a Snow Gundam that blocked the flames before they reached Wasabi and Abby. "You rock, Elsa!" Abby called out. Wasabi nodded, awestruck. The Gundam fired water, utterly drenching Tadashi.

Tadashi then lunged at Hiro, pulling out a sword Hans knew all too well. Time seemed to slow down as Baymax ambled toward Hiro. Abby and Wasabi in midscream. The Gundam faltering due to Elsa's utter horror. Tadashi's regular eyes flickering in and out as he struggled against the spell. Hiro shut his eyes, expecting the flames to engulf him. And then, he slowly opened them, confused. He couldn't make sense of what he saw next.

tbc