"If anything can go wrong-

it will."

-Murphy's law

Slight Warning: My dark humor came out this chapter and there's a war between drugged up quirks and physics.

(Physics loses, but that's only because those darn drugged up quirks prepared a trap card: Fictional-Fudging-Fantasy. Effects: Allows physics to turn on and off at will and you're a moronic imbecile who can't accept that it's LSD-powered-quirks and green paper/shiny bling-blings that make this world go round, not like actual gravity.) 

...

Beware.

"And let's not forget about the fact that you have essentially forced me to act. It was a promise all but in name, so I have no choice but to continue to fight," He let the lightning gathering underneath the white skin of his palm rise to the surface. "I wonder how your students will fare facing the true might of my quirk. I'm sure you've felt it already, haven't you? All you've done is made the situation worse."

He faced straight forward, the color of indifference coating his face, with only the slightest of twitches suggesting the sheer depth of his emotions to the world. He even resorted to putting his hands behind his back to prevent the erratic spasms from being seen.

Although, they may be signifying something contradictory to your current line of thought. 

'...I can't believe I managed to keep a straight face through all of that BS. What 'It was a promise all but in name'? Either I said 'I promise' or I didn't. Which I didn't in this case. There's no point in playing around with them anymore. It's not like I'll get a prize or something. That's just being stupid and not knowing when to quit. Regardless, I need to give Kurogiri some time to recharge, so this must be done despite my reluctance.'

A chilling, bone-cold smile appeared on his face as he thought of that possibility. Being accidentally launched into space, gaining some kind of unknown tumor/missing limbs when reassembling in another location, and even warping to an entirely new world was possible. Considering that Albert Einstein proved that general relativity was a thing (i.e. matter and energy distort spacetime) and that technically a pickle on a high shelf experiences time at a faster rate - no matter how minutely - than a pickle on the floor...

The on drugs, magic fog version that was unlogical as it was powerful, that was entirely based on unknown phenomena and instinct, was just as liable to magically screw-up as it had magically appeared. It was already the 23rd century, but Scientists still hadn't cracked the mystery that was quirks (Although to be fair, the Dark Ages had resulted in a substantial loss of written and digital knowledge alongside the people who knew how crude worked, so the technological standard was still around the 21st century).

Deku had heard stories of Scientists who committed suicide out of despair because of the clash between physics and the crazy abilities shown possible by quirks. For example, "A cactus doesn't have a brain! H-How can it think, have a personality?!", and "Where did the kid's original head go to?! How does he eat? Is it just photosynthesis or something? B-But it's just the head, he still has other organs...".

("Ah! But there is a species of cactus with a brain, Cylia~!"

"Shut up, you know as well as I do that this cactus head's species - if I can even call it that... - has never been seen before. Just like the rest of this shi-... Ahem, currently unexplained phenomena bequeathed to us from nature itself. I'm honestly just hoping that this me and acid having a particularly fantastical trip. Otherwise, it would mean that all my nightmares came true all at once.")

Basically, magical fog powers - full LSD juice charge = possible amputation with a free tumor and/or a slow, aggravating death in space.

It was only natural that he wanted to avoid the whole equation in the first place, right? He wasn't exactly eager to constantly use the variable either, but he didn't really have a choice in the matter. In any case, time continued to pass throughout this entire detour about the radioactive magic fog, and with it, the theatrics grew ever more grandiose and stupid. Deku was on the verge of hitting something. Hard.

Using an elegant and quick signaling method (read: frantic thumbs up or thumbs down gestures), Deku finally heaved a sigh of relief at the wispy thumbs up Kurogiri made after his second time checking in. He held a hand up in the middle of Aizawa's grand speech on how he couldn't trust him to leave Urakaka unharmed when he was screaming about killing Bakugo a few seconds prior - it was actually a pretty good point - and Aizawa quieted down like they had rehearsed the damn thing. Or maybe it was because his hand was sparkling with lightning. Who knew?

"I'm afraid I must hold myself true to my words; okay, now's the time, Kuro!"

Kurogiri's magic fog expanded outwards in an instant, and his ears just barely picked up the muffled reply (scream) from the other side.

"...What about all of that 'I must hold myself true to my words!"

He lightly smiled to himself.

"I don't take value in words unless they are a promise. But the thing is, I don't recall ever making a promise either-"

He was cut off mid-sentence.

"Bakugo, what are you-"

He hurriedly popped his head out of the fog, only to see a figure with no surprise on his face flying through the sky as a result of the combustion on the tips of his fingers. If it was only that it be fine, but he was flying straight into the magic fog. At this rate, he'd get into the portal before Kurogiri could teleport away to the hideout. And if he inevitably ended up at the hideout...

'Shigaraki would probably eat him alive, and I wouldn't be able to stop it. That damn stupid... Augghgh'

"Kuro, change the destination immediately!"

The fog shifted in a way that almost screamed unease.

"If I change the destination that quickly, there's no telling where it would send us to."

'...You've gotta be kidding me. Does the universe have a twisted sense of humor?! After all that time I spent thinking about everything that could go wrong, this happens? Still, I can't let Shigaraki get his grubby little paws (of doom) on him... Whatever, I'm suicidal anyway.'

"...Do it. It doesn't matter where we end up, or if we end up whole for that matter."

The blonde explosive freaky child charged in a second after the decision was made, and the Ark of Noah was sent spiraling off into a random body of sea, as so directed by its captain. Meanwhile, as Deku lay in the embrace of the seemingly infinite fog, he felt like puking. If the normal transit was simply letting the ground pull you forward, this was a messed up trampoline park that was incredibly hard to grasp your bearings in. Up felt like it was down, right felt like left, and you're sense of balance was totally annihilated. Sometimes it felt like his body was being stretched or squeezed in inhumane ways, only for it to dissipate like an illusion a second later.

This hell continued for approximately 15-20 seconds before they were upchucked into the outside world.

"Oh, thank god... All of my limbs are still attached..."

He forced open his sagging eyes once more, fighting to keep his awareness amid nausea and sheer relief. 

'And I don't think I have any tumors, nor am I in space... I'm sorry for doubting you, Kurogiri's quirk.'

"That was close," Deku eyes fell on Kurogiri's wispy persona like the lightning that was his quirk. "I thought that we were going to be dumped in the sea for a little bit there. Perhaps around 700-800 feet underwater. Fortunately, I managed to drag us away."

'...Suddenly, I feel very warranted for being worried. 700-800 feet underwater is more than enough to kill a human. Many times over.'

He turned away from Kurogiri to survey their new environment - his definition of safety was a little too loosely defined from Deku's taste - only to feel... bizarrely nostalgic? It was a playground with a theme of red and blue, although the colors were a little faded. It looked like it hadn't been truly played on in years. There was a jungle gym, and there was a... big tree in a clearing...

"This is..."

Another voice spoke the truth before he could.

"T-that playground..."

Omake:

He fell out of Kurogiri's black purplish fog with a severe sense of disorientation. He had blacked in and out while inside the portal user's fog during the transit and felt incredibly uncomfortable now. He leaned on his side as he dry-heaved, seeking to get rid of acidified food that didn't exist in his stomach. He wasn't quite sure why it had been so uncomfortable; fearing the worst, the first thing he had done upon his first lengthy period of awareness was to check for any injures or things out of place. But there was nothing, no amputated arms, or tumors (as far as he could tell). He wasn't in space either, that was pretty certain.

He couldn't find Bakugo or Kurogiri either. He highly doubted that they would both unanimously decide to ditch him (The blonde was incredibly stubborn, and Kurogiri was just loyal like that). That meant that... either they were both blown to space dust smithereens (unlikely considering he was still alive) or there was some unforeseen circumstance. That theory was reinforced ten-fold as he stared into exquisitely cut, green, gem-like eyes.

"A-Are you okay?"

AN: Okay, thanks for living through my mini science lessons, and my rather apparent frustration with Kurogiri's magic fog. I can literally live with anyone else's quirk, but for some reason, his just makes me mad. (Maybe because it's spacetime LSD juice-, okay, I've used that joke too much today. Hahaha.)

I think you've got a pretty good picture as to who our mystery friend in the omake is. To be honest, it sounds like a pretty fun plotline to explore, so if you guys just want an omake for the next chapter, I'm totally game. Or I can just continue the Bakugo - Deku confrontation. I'll do a poll, so the fate of the omake is in your hands!

Please hit those hearts and leave a comment before you go! Peace out~

CLARIFICATION: The omake is not time travel, but rather ALTERNATE TIMELINE TRAVEL (or just the original story timeline, if you prefer). An omake is a scene that's not part of the main storyline, but still has some connection to it.