10 minutes earlier...

Strange had been minding his own business, sitting on the back garden of the Sanctum, simply having some peace and quiet away from wizardry. He'd been thinking about everything crazy that had gone on recently, what with the excursion to Las Vegas in another dimension with Loki, Wanda Maximoff and Scott Lang. They'd taken down his old friend-turned-enemy Mordo about a week ago, who was now in jail in Kamar-Taj (and he didn't even know Kamar-Taj had a jail). It had been... eventful. Since then, his legs had healed and he still had his magic back. It was nice to not have to worry about anything, after all, Hawkeye, T'Challa, Captain Marvel, among over Avengers, had assured him they didn't need his help. He was sure they'd be fine, apparently it was only a small alien invasion, and they had some wizards to help them out.

Nah, he could just sit here and watch the birds and butterflies fly around, chased by his magic cloak, without a care in the world. It was a lovely summer day, last week was all horrible and miserable with that stupid rain that got you absolutely soaked.

Wanda must've had the same idea as him, as she'd gone back to wherever she was living currently, apparently to chill and do some "light reading". Scott was another Avenger who hadn't been called into Las Vegas. He was doing some Quantum Realm stuff with Hank, Janet and Hope (he still didn't know who they were). Loki was doing whatever gods did in their spare time.

It was all great until something interrupted his day-dreaming. Namely a golden swirling portal appearing right in the middle of his garden. Through it walked his fellow wizard, Wong, who'd been one of the wizards helping the Avengers over in Vegas. Just that fact made him certain something was wrong, well, that and the very worried look on his normally expression-less face.

"Strange, you have to come now," he told Stephen. "Something's... happened."

Strange stood up and said urgently, grabbing his cloak, "What happened?"

"Er... you'll see," Wong told him, and Strange followed him through the portal into Las Vegas... er... the desert?

He knew Vegas was in the desert of course. When he and the others had gone to the one in the other dimension not long ago, he'd accidentally opened a portal a mile from civilisation itself. This reminded him of it. The sun was harsh and blinding, the heat was sweltering, and they were in the middle of nowhere. He missed the sunglasses Loki had made for him when they'd gone last time, even if they didn't suit him. But something was wrong...

Hawkeye, T'Challa, Captain Marvel, Falcon and War Machine were waiting there, among several of his wizard colleagues. Everyone had an identical worried expression on their faces, but Stephen still couldn't figure out what was so... wrong. Everything seemed fine to him. But why were they in the middle of the desert when they should've been fighting off aliens in the city?

"Sorry to disturb you, Dr Strange," Hawkeye apologised. "But um... he said you might know what to do and... we have no idea how to um... bring a city back."

Stephen blinked. "Bring the city back?" he repeated.

Then it hit him.

"Yeah... we did a spell and it clashed with the aliens' magic," Wong started, "and the city... vanished. Captain Marvel convinced the aliens to go back to their own planet, but now... we don't know how to get the city and its people back."

Strange looked around them and exhaled. "I have an idea. It could work, but..." He paused, thinking it through. He'd briefly read a spell the other day, glanced at it as he flicked through one of the spell-books. He couldn't remember the warnings, but he could remember how the spell was performed, and if it worked...

"Yeah. Let's try it," he decided.

Strange explained the spell to his wizard colleagues, as they'd have to work together and share the power for it to work effectively. And well... it was hardly a dramatic spell. No flashing lights, no angelic glow, no music from the heavens. The city simply reformed around them, as though it had popped up from the ground in under a second. People reappeared, blinked a few times, then carried on with their days as though nothing had happened. Stephen immediately felt light-headed with the use of so much magic, but didn't faint or stumble.

It had really worked. He hadn't expected that.

Captain Marvel looked impressed. "Awesome work. How'd you do that?"

Stephen had just shrugged, "Magic," before something strange happened. The ground trembled under their feet, the rumble growing stronger. The sky was darkening, dark clouds appearing from nowhere. Strange looked up, everyone looking as confused and worried as he felt. Even the citizens had noticed something was wrong. Was it an earthquake?

Then T'Challa tapped him frantically on the shoulder, saying, "Um, that wasn't there before, guys."

Everyone turned around, and Stephen had to catch his breath. He was seriously regretting this already. For, materialising before their very eyes, right out of the ground, was what seemed to be a new hotel/casino. That didn't sound like a problem, but it was about 200 storeys tall, shaped like a jagged spire of rock, as though touching the sky. More than that, the walls were made entirely from fire, and the sign outside said, 'The Casino Mephisto'.

Uh oh.

"Uh, Stephen?" said Wong, his face even more anxious than Strange had ever seen it. "What did I tell you about reading the warnings?"

"What's Mephisto?" asked Hawkeye, readying his bow and arrow, which would be of no use here.

Strange gulped. "The devil," he replied. He felt everyone's eyes turn to him, and felt pressured and as though his face was on fire, though that could've been the heat from the new hell building. "He, er, can steal your soul and condemn you to eternal torture. Or he used to, but now I think his profession's changed to, er, casinos. Apparently."

"You literally bought Hell to Earth?" asked Falcon in disbelief.

"Er, yeah. I guess you could say that."

"So what now?"

Strange couldn't think straight. The 60 degree heat combined with the light-headedness of casting the spell combined with the sound of screaming from the citizens had that effect on his brain. For the first time since he'd made the decision, he regretted not taking the time stone from the other dimension. Something like that would really come in useful right now. "I don't know. I'll fetch help. Can you all protect the city in case anything comes out of there?"

Captain Marvel brought her magic to her hands and started doing the glow-y thing she always did. "You can count on us, Doc. Do what you gotta do."

"Thanks, guys. I'll be back." Stephen opened a portal, leaving behind the sound of screaming and Avengers fighting whatever horrors came from the newest Vegas attraction, desperately hoping they could hold off whatever it was without getting their souls condemned to eternal torture.