So, 30,000 words (70-ish pages) into the current fic-in-progress, this came to me and would not leave me alone. I hope it makes you smile.

This is AU, crack, Alternate Universe, intended only for a laugh in these distinctly unfunny times, and ALTERNATE UNIVERSE. Things happened (and happen) differently herein than they did in either MCU or HP canon.

All rights to this work are hereby given to the respective copyright owners of the Marvel Cinematic Universe, the Marvel comics universe, and Harry Potter.

Just as Thanos is about to snap his fingers, an unexpected visitor arrives.

Thor Odinson snarled as he forced Stormbreaker's blade deeper into Thanos's chest. The Mad Titan stumbled, almost collapsed, and triumph sang through Thor's veins.

Then Thanos lifted his gaze to meet Thor's.

"You should've gone for the head," he said and time stilled as he raised his left hand, the hand with the Infinity Gauntlet and its six stones in place, and brought his thumb to his middle finger.

The snap never came.

Thanos appeared to be struggling to snap his fingers, but they wouldn't move.

"What sorcery is this?" Thor muttered.

"Magic, really, more than sorcery."

The voice, a pleasant tenor, came from behind him, and Thor ripped Stormbreaker from Thanos's chest as he whirled to face the speaker-

-and found himself staring at an unassuming young man almost a foot shorter than he was, with messy black hair, wire-framed glasses, and wearing jeans, a T-shirt, and a coat and boots made of some kind of leather.

"He was right, though," the man said. "You should've gone for the head. Or the glove. Arm, even - anywhere that would've kept him from actually snapping his fingers."

"And what," Thor demanded as the others assembled to fight Thanos - Avengers all, whether or not he'd yet met them - made their way toward the three of them "is preventing him from snapping his fingers now?"

"I am," the man said and offered a smile.

"And who," asked Steve Rogers, Captain America, "are you?"

"Oh, right. Sorry." He offered his hand first to Thor. "Harry Potter, Master of Death, at your service."

Bemused, Thor shook the man's hand, keeping his other hand on Stormbreaker, just in case. "Thor Odinson."

Steve shook Potter's hand as well and nodded toward Thanos. "He seems to want to say something."

And it was true; Thanos's facial muscles were straining against some unseen force.

Potter turned to face Thanos. "What?" he demanded.

"If you're the Master of Death," Thanos said, his breath wheezing thanks to Stormbreaker's destruction of his chest cavity, "then you know …"

"That you were about to kill half of the living beings in this universe?" Potter asked with a truly sarcastic raise of one eyebrow. Loki would be impressed. "Yes, I know."

"Do you also know why?" Thanos rumbled.

"No," Potter replied immediately. "And I'm not sure I care."

"It was for her," Thanos said, and his tone had a desperate edge.

"Her?" Potter frowned, puzzled. "Who's her?" He turned to Thor. "Any ideas?"

"Nay, none," Thor replied.

"I'm not sure I want to know," Steve murmured.

"So?" Potter demanded of Thanos. "Who's her? Or, properly, who's she?"

"The one you serve," Thanos said. "Death."

Potter snickered. "You poor, deluded sod."

"Deluded?" Thanos roared, but the effect was diluted by the wincing cough that mostly replaced the final syllable. Thor adjusted his grip on Stormbreaker, just in case.

"How dare you call me deluded?" Thanos demanded, his voice less powerful than it had been. "I am the only one with the vision and the will to carry out what must be done to save this universe."

"By killing half of its occupants," Potter said.

"I can imagine no more fitting gift for my lady Death."

Thor found that … disquieting. Unsettling. Perhaps even, as Darcy Lewis would say, creepy. So he wasn't prepared for Harry Potter to burst out laughing.

Neither, apparently, was Steve, who frowned. In his full Captain America regalia, it was an impressive expression. "This is no laughing matter."

"It's really not," Potter replied, still chuckling. "Except it kind of is."

"That makes no sense at all," Steve said, and Thor had to agree.

"Out of context, no," Potter said. "But what if I told you that rather than being female, Death is in fact a rather cadaverous looking fellow who drives a '59 Cadillac and has an unhealthy appreciation for Chicago deep dish pizza?"

Thor felt his lips twitching, but before he could laugh, Thanos roared, "Lies!"

"I'm not," Potter said. "And as Master of Death, I rather think I have more knowledge on the subject than you."

"What does that mean," Thor asked, "Master of Death?"

"I'm not entirely sure," Potter said, and Thor shared a puzzled glance with Steve. "My former mentor said it was the capability to accept death and even willingly embrace it. Considering how hard I've fought to stay alive sometimes, I think he was rather barmy for suggesting it."

"And since you've become Death's master?" Thor asked, genuinely interested.

Potter chuckled again. "I don't have much more than that. I live my life, and occasionally answer his call to deal with bothersome upstarts like this one." He waved a hand toward Thanos. "I'm starting to believe it has more to do with mastering the fear of Death - because he can be a right terrifying arse when he wants to be, and I grew up facing terrifying arses, so …" Potter trailed off with a shrug.

"'Tis wondrous strange," Thor said. "Mayhap, when this … arse … is dealt with, I can meet your Death?"

Potter looked surprised by the request. But then, Thor admitted privately, not many beings would want to meet Death.

"I can't promise," Potter said, "but I'll ask."

"That is all I can ask," Thor said. "Tell him Thor Odinson sends his regards - and his thanks, for sending you to deal with this arse."

"Speaking of this arse," Steve said, bringing Thor's attention back to the moment at hand.

"Right," Potter said, and turned back to Thanos. "Do you understand why Death sent me?"

"No," Thanos said. "I was prepared to give her the greatest offering anyone ever could! Why would she stop me?"

"Again, not a she," Potter said. "And as to the why…. You seem to believe that Death wants people to die."

"Of course!" Thanos replied.

"That's partly correct," Potter allowed. "Your error is in thinking that Death wants people to die indiscriminately and in great quantity. Nothing could be further from the truth."

"I - don't understand," Steve said.

"Death is, as Shakespeare put it, the necessary end," Potter said. "It comes to all of us in the end - even Death himself will die at some point and in some way none of us can understand. Death is part of the natural order - until some arrogant twat thinks he knows better than Death."

The glare Potter sent Thanos was truly impressive. Thor credited Thanos - albeit grudgingly - for not quailing under its weight.

"So - what now?" Steve asked.

"Now, I deal with this twat, and hope the next one has the decency to wait until someone else is Master of Death," Potter replied.

A realization struck Thor, and he asked, "Why has Thanos not moved?"

"Do you want him to?" Potter asked. "I can release my spell, if you like."

"Spell?" Steve frowned, but Thor only nodded. Seiomenn were known throughout the Nine Realms, though he hadn't realized Midgard had any.

"And what will you do with the Mad Titan?" Thor asked.

"He'll get his wish," Potter said, with a grin that danced along the border between mischievous and evil. "Death wants a word with him."

"And the Gauntlet?" Steve pressed.

"What about it?" Potter asked.

"It - or rather, the Infinity Stones contained within it - gave him the power to do what he wished," Thor said.

"What do you want done with it?" Potter asked, his gaze flicking from Thor to Steve, and then past them to the rest of the assembled Avengers.

"Please -" a figure in red shoved between Thor and Steve. Thor took a moment to remember, then recognized the woman as Wanda Maximoff, whom they'd met in Sokovia. "Vision was killed when Thanos took the Mind Stone from him. I don't care what you do with the other stones or the gauntlet, but please - can you return the Mind Stone to Vision?"

"Who's this Vision, and where is he?" Potter asked.

"Over here." Wanda led him a short distance through the Wakandan forest, and Thor winced as he saw the husk of what had once been the Vision, a construct capable of containing the Mind Stone, with as solid a moral code as he could hope for.

Potter stood staring at - it? him? - Thor didn't know what was appropriate - for a long moment, frowning.

Finally, he said, "Well, that's a challenge."

"Please," Wanda begged.

"I'll try," Harry said. "But because he wasn't fully organic, he's not dead, if you take my meaning. I'm not sure what I can do. Accio Thanos."

It was only then that, to his eternal shame, Thor realized he'd completely forgotten about Thanos and the threat he presented. That Potter hadn't been concerned was no solace at all.

A few surprised cries and yelps behind him made him turn, only to smile as he saw Thanos, still frozen in the same position he'd been in before Thor followed Wanda to this clearing, still with Stormbreaker lodged in his chest, floating toward them.

Judging by the Mad Titan's expression, Thanos appeared to be shouting something, but no sound came out.

Thanos came to rest beside Vision, and Potter looked between them for long moments, muttering to himself quietly enough that Thor couldn't make out the words.

"Right, then," Potter said aloud after a few minutes of muttering. He held out his left hand and turned a ring - a ring that Thor hadn't noticed before - on his third finger three times.

Thor tensed as an apparition appeared before them. It swirled and surged, eventually coalescing into -

"Vision!" Wanda cried, and started forward, only for Steve to catch her arm and hold her back. She turned a glare on him, but Steve held her firmly.

"Probably better not to interfere," he said, and after a second, she nodded and relaxed in his grasp.

"Thanks," Potter said absently. His attention was focused on Vision. "Do you understand why I summoned you?"

"I do," the apparition responded.

"And your choice?" Potter asked.

Vision looked at Wanda rather than Potter when he said, "I would like you to try."

"You understand the risks - not least is that I'll fail?" Potter spoke more somberly than he had to this point, and the apparition of Vision turned to him.

"I understand," Vision said. "But there is little I would not risk to have Wanda in my arms again."

Potter smiled. "I understand."

"Wanda," Vision said, "if the Master fails in his attempt -"

"He won't," Wanda said fiercely. "I won't let him."

"It is not your choice," Vision said softly, and Thor looked away from their intimacy. He still had hope for such a relationship himself and would not want strangers watching a moment like this between him and his beloved.

"If he fails," Vision repeated, "then this is what was meant to be. I will watch over you as much as I am allowed."

There was a moment of silence, and from the corner of his eye, Thor saw Vision reach out a spectral hand and trail a finger down Wanda's cheek. Then the apparition faded.

Harry Potter was already focused on Thanos. More specifically, he was examining the Infinity Stones with some interest. "Which is the Mind Stone?"

"The blue one," Steve replied. "This may be a dumb question, but why is Thor's axe still stuck in his chest?"

"Because I'm not ready for him to die yet," Potter replied. "He has a date with Death first. When I'm done with … Vision, you called him? Then I'll put him in stasis and Thor can retrieve his axe."

The warrior in Thor agreed with Potter's strategy with respect to Thanos. As long as the Titan couldn't break free of whatever had been done to him - and surely he would have by now if he could have - leaving him as he was made sense. Steve looked somewhat dubious, but chose not to say anything else.

Minutes later, Potter had removed the Mind Stone from the gauntlet - Thor wasn't quite certain how - and turned back to Vision. He put the Mind Stone in the gash left in Vision's forehead when Thanos removed it and said, "Reparo."

Thor watched in some amazement as the gap in Vision's forehead where the stone repaired itself, the stone sinking into place. The husk of Vision's body remained inanimate, the colors muted, though, and Thor grieved again for the being he'd known so briefly.

Potter frowned, flicked his wrist, and a stick not quite a foot long appeared in his hand. He pointed it at Vision and said again, "Reparo."

This time, Vision's body was enveloped in a soft glow, and the colors of his body brightened just a little.

"Stubborn, are you?" Potter asked with a wry twist. "I'm no better." Another flick of his wrist, and the stick he held was replaced by one a little longer. He pointed the new one at Vision and said a third time, "Reparo."

A brighter glow enveloped Vision's body, and as its colors brightened Thor could only breathe, "By Odin Allfather…."

Beside him, Wanda made an inarticulate sound and started forward, only to be stopped by the grip Steve still had on her upper arm.

"Wait," Steve said. "I don't think he's done yet."

Indeed Potter wasn't. He raised the wand - for it could only be such, Thor decided - and aimed it once more at Vision.

"Et nomen mors, ego non recuso. Ut curari nequeas."

A grass-green glow surrounded Vision's body, fading to a pure white after a time Thor chose not to estimate.

Finally, the glow faded entirely, and Vision's body appeared to relax completely.

A minute later, Potter jabbed his wand toward Vision. "Rennervate."

Vision gasped hard, and convulsed almost to a sitting position. Wanda jerked free from Steve and flung herself at him, throwing her arms around him.

"That's a job well done," Potter said quietly, smiling gently. "My job's rarely so pleasant."

Thor hated to intrude on either the happy couple or Potter's satisfaction, but there was one question that still needed an answer. "What of the other stones?" he asked. "They cannot be destroyed."

"But they can be scattered," Steve said. "That we had so many on Earth is … troubling."

"Are the stones dangerous without the gauntlet?" Potter asked.

"The gauntlet contains, directs, and amplifies their power," Thor replied.

"That would be yes, but not nearly as much," Steve said.

"Easy enough," Potter said. He pointed the long wand at the gauntlet. "Accio Infinity Stones."

Thor watched the stones shudder in their settings and then fly toward Potter who caught them with so little effort it seemed he wasn't even watching them.

The wand aimed at the gauntlet. "Reducto."

Thanos's hand, and the gauntlet sheathing it, disintegrated into a fine mist, and Thanos screamed - or so Thor assumed, based on the Titan's expression, as no sound emitted from him.

"Scourgify," Potter said, and the mist vanished. "Episkey." The stump of Thanos's wrist sealed as the bleeding stopped. "That takes care of that. Can you take care of the other stones, or should I?"

Thor looked to Steve, who frowned in thought for a moment before saying, "Do you have access to other worlds? Other … planes of existence?"

Potter looked surprised. "I might. Death certainly does."

"Then you should take at least one of the stones," Steve said. "Take it to another plane. That should prevent anyone from uniting them all again."

Potter hesitated only a moment. "Any preferences which stone?"

"The Reality Stone," Thor said. "It is the only one I have direct experience of. Removing it from this dimension will not affect anything else, as it was in the hands of the being called the Collector - who, I believe, has been grievously injured and is no longer a competent guardian of the stone."

"Any objections?" Potter asked. No one moved so he nodded. "Right, then - which one is that?"

"You don't know?" Natasha Romanoff blurted from where she stood beside Bruce Banner.

"Should I?" Potter countered, and Natasha blinked, clearly surprised by the man's reaction.

"The red-hued one," Thor said, and a moment later, Potter offered four of the stones to him, keeping the Reality Stone in his hand.

"Right." Potter flicked his wrist once again, and his wand disappeared. "Is there anything else you'd like me to take care of?"

Thor exchanged a frown with Steve. Steve was the de facto leader of the Avengers, but Thor supposed he had more knowledge of the worlds beyond Midgard, so he should be Steve's closest advisor in this instance.

He took that position seriously, even if the others might not consider it, and thought the situation through as best he could.

"There is one thing," he began, and Steve's eyes widened.

"The invaders," Steve said. "The ones who came with Thanos. Maybe they'll back off if they know their leader's … incapacitated. But if they don't…."

"Ah." Potter smiled grimly. "I think you'll find you have more assistance there than you're aware of. This one-" he gestured at Thanos "-made Death a bit cross."

"That seems … unwise," Thor said.

Potter snorted. "It doesn't happen often - the last time was the prat who started the Black Plague. Even Hitler and Grindelwald at their worst never did more than irritate Death. The point is, sometimes, Death has to step in to right the natural order. I expect when you contact your allies, you'll find everything is in hand."

There seemed little to say to that, and by the expressions on Steve's and Natasha's faces, they agreed with Thor's conclusion.

"We are grateful for your assistance," Thor said finally, all his mother's training on manners and comportment asserting itself now that the fight appeared to, however unexpectedly, be over.

"Right, well," Potter looked distinctly uncomfortable and the gratitude, and Thor wondered at the reasons behind that expression. "Happy to help, just doing my part, and all that."

"What now?" Steve asked.

"Now?" Potter gave another one of those grim smiles. "Now I take this arrogant tosser to fulfil his wish to meet Death. I don't expect it's going to go how he planned. Pleasure to meet you all, and if we have to meet again, let's hope it's for a pint, yeah?"

"First round's on me," Steve promised and offered his hand.

Potter shook it and turned to Thor. "Great meeting you, Prince of Asgard."

"And you, Master of Death," Thor replied, clasping the other man's hand.

"Oh, right - can't forget your axe." Potter turned and raised his hand to point at Thanos.

As Thor watched, Stormbreaker came free of Thanos's chest and flew toward him.

"Sanguinus stasis," Potter said, and a dull gray aura surrounded the Titan. Potter turned and pointed at Stormbreaker. "Scourgify."

When Thor caught Stormbreaker, it was clean of Thanos's blood. Death's Master was unfailingly courteous, it seemed.

"I think that's got it," Potter said, pocketing the Reality Stone and glancing around. "We're off to Chicago, then."

Potter grabbed Thanos by the upper arm, nodded a farewell, spun in place and disappeared.

"So," Bruce Banner drawled. "That happened."

"It did," Steve said. "And now we just have one question."

"Just one?" a number of the others chorused.

Thor smiled briefly. "One important question."

Steve nodded. "What do we do with the other four stones?"