In the MCU/Marvel with the Omnitrix/Ultimatrix

The tower feels strangely quiet. Thor's off somewhere with Jane Foster (probably destroying another coffee shop's supply of pastries), Emma's been dragged shopping by Pepper (something about "expanding her winter wardrobe"),

Banner's off letting Hulk go meet Penguins (something he's constantly being complaining about) and Tony's at some tech conference in Tokyo.

Which leaves me alone with Loki.

The one called God of Mischief sits in the common area, reading what looks like an ancient tome but is probably just glamoured to hide whatever trashy novel he's actually enjoying.

"Bored?" he asks without looking up, a slight smirk playing at his lips.

"What gave it away?"

"You've transformed into three different forms in the past hour just to raid the kitchen from different angles."

I can't help but grin. "Well, someone had to test if Stark's security system could track multiple forms at once."

"And did it?" Now he looks up, that particular gleam in his eyes that usually means trouble.

"Nope. Though I may have accidentally convinced JARVIS that we had a break-in when I used Big Chill to phase through the fridge."

Loki closes his "ancient tome," and I catch a glimpse of what looks suspiciously like a romance novel cover before the glamour reasserts itself. "You know... there are more interesting ways to test security systems."

"I'm listening," I say, though something tells me I probably shouldn't be. Then again, when has that ever stopped me?

"Well," Loki sets his book aside completely, "I've always wondered if Stark's AI could track simultaneous illusions and transformations. Purely for security purposes, of course."

"Of course," I agree, already scrolling through the Ultimatrix's options. "And I suppose replacing all his coffee with illusions while actually hiding it using Upgrade would be a good test?"

"My, my," Loki's grin grows wider. "And here Thor thinks I'm the bad influence."

Three hours later, we've turned the tower into what can only be described as a prankster's paradise. Every mirror shows a different reality, the coffee machine makes smoothies but insists they're espresso, and I'm pretty sure we've convinced JARVIS that the word up is means down.

"Amateur work," Loki critiques as I use Upgrade to make all the phones play 'Thunder' whenever Thor tries to call. "Though I appreciate the sentiment."

"Oh really?" I transform back to human form. "And I suppose you could do better?"

His smile turns dangerous. "Is that a challenge?"

Looking back, maybe challenging the one literally worshipped since old as the God of Mischief wasn't my brightest move. But in my defense... actually, no, I have no defense. I just really wanted to see what would happen.

"Your illusions are impressive," I admit, watching him create a perfect replica of Tony doing the macarena in the lab. "But can they do this?"

I transform into Upgrade, merging with the tower's systems to make every screen display increasingly ridiculous memes about the Ultimates, especially, Loki who's expression shifts from amusement to genuine interest.

"Technology manipulation for mischief is Interesting. Though perhaps you're using it a bit... local in scope."

"Local in scope?" I separate from the systems, transforming back. "What exactly did you have in mind?"

His grin turns positively wicked. "Well, there is this lovely little planet in the Nine Realms where the inhabitants take themselves far too seriously..."

"Are you suggesting we take an intergalactic pranking road trip?"

"I'm suggesting," he corrects smoothly, "that we conduct a thorough test of your new forms' capabilities in various environments. If that happens to involve some creative chaos..."

I should say no. I really should. But...

"JARVIS, if anyone asks, we're conducting important interdimensional research."

"Of course, sir. Shall I inform them you're definitely not planning cosmic-level pranks with the God of Mischief?"

Even Loki looks impressed by the AI's sass.

"So," I ask as Loki opens a pathway between realms (way more elegant than the Bifrost, I'll give him that), "exactly how much trouble are we going to be in when Thor finds out?"

"Please," he scoffs, stepping through the portal. "My brother once turned an entire diplomatic meeting into a drinking contest. He has no room to judge. Besides, at least this time, there for sure won't be a war on the horizon." he mutters the last part.

And I can give him that. Thor was quite the idiot with the whole Frost Giant fiasco - Loki being the cause, not making him blameless.

I follow him through, transforming into Jetray to keep pace as we emerge in... wow. The sky here is literally made of crystals, reflecting light in impossible patterns.

"Welcome to Crystallos," Loki announces with dramatic flair. "Home to the most uptight beings in the Nine Realms. They once banished someone for laughing too loudly at dinner."

"Let me guess," I begin, already scanning the crystalline architecture. "They're not big fans of creativity?"

"They have laws about proper cloud appreciation procedures." His tone carries centuries of pent-up mischievous urges. "Shall we... enlighten them about the joys of chaos?"

I begin thinking about Upgrade, again. "You know what happens when you merge living technology with crystalline structures?"

"No," his eyes gleam with interest. "What does happen?"

"Let's find out." I state with a grin as I tap my chest.

Turns out, merging Upgrade with crystalline architecture creates what can only be described as a cosmic light show. The entire city's structures start pulsing with patterns that would make Times Square look subtle.

"Their faces," Loki wheezes between laughs as the local council members run around trying to restore 'proper luminescent dignity' to their buildings.

"I haven't seen anyone that scandalized since Thor wore his ceremonial cape backwards at the All-Father's feast."

I separate from the crystal spire, transforming back. "Please tell me you have pictures of that."

"Better," his grin turns devious. "I have illusions."

We spend the next hour causing what Loki calls "creative disruption" and what I'm pretty sure most people would call "interdimensional mayhem."

The crystal beings' perfectly ordered society descends into beautiful chaos - their meditation fountains now play rock music, and their paths rearrange themselves like puzzle pieces - leaving their sacred structures and the like aside, don't wanna really hurt people after all. 

"You know," I say as we watch a group of officials try to catch what appears to be a dancing crystal tree (courtesy of my brief merge with their plant life),

"you're actually being an awful influence. I'm supposed to be the uptight, serious hero with the mightiest power in the universe at my fingertips, and yet here you are, convincing me to do this."

"Please," Loki smirks, creating an illusion of the officials doing a synchronized dance routine, "we both know you're enjoying this far too much to play the responsible hero card now."

"Although," Loki adds, watching his illusions merge perfectly with my technologically enhanced chaos, "I must admit, for someone with such potentially devastating power, you have an impressive talent for... creative applications."

"Coming from you, I'll take that as a compliment." I transform back from Upgrade, admiring our handiwork as the crystal city sparkles with unauthorized joy. "Though maybe we should move on before they figure out how to track interdimensional pranksters."

"Worried about your heroic reputation?"

"More worried about Emma's face when she finds out I helped turn an entire alien civilization's structures into expressing dancing memes."

Loki's eyes gleam again, "There are these delightful floating islands in Alfheim..."

"No," I say firmly, then pause. "...what kind of floating islands?"

"The kind that change color based on emotion. Very dignified place. Very proper. Very..."

"Very in need of some chaos?"

His grin is answer enough. As he opens another portal, I can't help but think - maybe we both needed this. A break from being the serious ones, the planners, the ones who carry the weight of future knowledge.

Sometimes you just need to make some cosmic mischief.

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(Author note: Hello everyone! I hope you all enjoyed the chapter.

Do tell me how you found, Samael and Loki this chapter.

They are after all, the biggest planners in the team, Samael having the future knowledge and aliens smarter than even Tony and Banner, and well, Loki, being Loki, who may or may not know a lot more than he is letting on.

I wanted to make a more down to earth, light hearted chapter. Away from all the seriousness and all that.

Hope it was fun.

I hope to see you all later,

Bye!)