Grindelwald had been at Stark Tower for a few days now, and things had settled into a strange but oddly comforting routine.
Tony had cleared out one of the luxurious guest rooms on the upper floor and given it to Grindelwald. The older wizard took to it with quiet grace, showing no arrogance or entitlement. He kept mostly to himself, though his door was always open when Harry came knocking.
And Harry did knock—a lot.
The boy was absolutely fascinated. While Tony provided tech, sarcasm, and waffles, and Sirius and Remus gave the warmth of chosen family, Grindelwald offered something different.
Magic history. Theory. Quiet, intense knowledge spoken like riddles wrapped in fire.
"Uncle Gellert," Harry would say, grinning (because yes, the title stuck), "what's the German word for dragon?"
"Drache," Grindelwald would answer patiently, handing over another thick, aged book. "But don't let the pretty word fool you. They're just as temperamental in any language."
And as much as Sirius and Remus tried not to show it—they were jealous.
Remus would peek in and see Harry furiously scribbling notes with Grindelwald correcting him gently, and feel a twinge of something he didn't like admitting.
Sirius pouted openly more than once, until Grindelwald offered to teach him some spells too.
"No dark magic," Remus warned.
"Define 'dark,'" Grindelwald replied with a half-smile.
Still, none of it mattered when they saw how happy Harry was.
Down in his lab, Tony had finally done it.
The suit was complete—not a traditional Iron Man suit, but one designed to channel and integrate with the magical core he'd been studying. Rune-etched plating, mana-conducting fibers, an arcane converter powered through the same core as his arc reactor. It wasn't perfect, but it was his first successful hybrid.
"Mark Magic-01," Tony muttered, stepping back with greasy hands and tired but triumphant eyes. "God, I'm good."
Tony was getting well with basic magic, Sirius offer to take him to Diagon alley to help him buy a wand, However, Tony refused. Because it didn't felt right.
The basic theories of magic were mapped out on his holo-displays—symbols, equations, incantations he'd spent weeks trying to make sense of. He didn't have magic like them but he could manipulate it through tech now.
He was just about to call it a night when Jarvis spoke.
"Sir, you have an incoming call from Doctor Foster."
Tony blinked. "Jane? What's she doing calling me at—" He looked at the time, then shrugged. "Alright, put her through."
"Tony, I need to warn you." it was Jane's voice.
"Well, that's never a good opener," Tony quipped, wiping his hands with a rag. "What's going on, Doc?"
"Thor's here," she said quickly. "He just… showed up in a bolt of lightning and demanded to speak with you."
Tony raised an eyebrow. "Me? Why?"
Before she could answer, Thor's booming voice came from the back.
"IS THAT THE SON OF STARK? TELL HIM I WISH TO SPEAK WITH HIM FACE TO FACE!"
Tony winced at the loud voice. "Okay, yep, he's still got the voice of a walking storm cloud."
Jane sounded apologetic. "He insists it's important. Something about power, changes in the realm, something about a 'gathering of forces.' I couldn't catch all of it. He's a little… dramatic."
Tony exhaled. "Right. Well, I can't exactly fly out there right now. Company stuff, Tell you what—Jarvis will send the private jet. You, Thor, whoever wants to tag along—come here."
Thor's voice echoed again. "YES! I shall descend upon his tower and we shall speak of destiny and fate!"
"Okay," Tony muttered. "Jarvis, coordinate with Jane."
"Already in progress, sir," Jarvis replied smoothly.
The call ended, and Tony sat down with a thoughtful frown.
"Thor showing up unannounced usually means something big," he murmured.
Then Jarvis spoke again, in that perfectly calm tone that always preceded something not calm. "Sir, Mister Grindelwald wishes to speak with you immediately. He claims he has found something regarding S.H.I.E.L.D. that you will find… exciting. Or in his exact words—'deliciously suspicious.'"
Tony blinked.
"Well that's not ominous at all."
————
The hallway leading to Grindelwald's room was dimly lit, not out of design but because the wizard preferred it that way. Something about "the mood helping concentration" or "natural shadows being more honest than artificial light." Tony thought it was dramatic nonsense—though he had to admit, it did look cool.
The door open and Tony walked in with a half-eaten protein bar and a mug of black coffee.
"Knock knock," Tony said, taking a bite. "I come bearing caffeine and emotional baggage."
Grindelwald sat cross-legged in the room's elegant armchair, a thick file open in his lap. He looked up with a smirk.
"I was beginning to wonder if you'd gotten lost in your labyrinth of wires and machines,"
Tony rolled his eyes. "Yeah, well, some of us enjoy indoor plumbing and electric toothbrushes."
They exchanged a chuckle before Tony noticed the file in his hands. The sharp glint in Grindelwald's eyes immediately put him on alert.
"You look like a man who just found something juicy… or dangerous," Tony said, approaching with narrowed eyes. "Or both."
Grindelwald held out the file.
"I suggest you read this."
Tony snatched the folder and began flipping through the pages. At first, the documents looked routine—intel briefings, intercepted communications, some names and call signs. But then his eyes landed on the unmistakable symbol burned into a scanned patch of leather:
A skull… with tentacles.
Tony froze. "…Hydra?"
His voice cracked through the silence like a dropped glass.
"No. No, no, that's not possible." Tony's brain raced. "Hydra was dismantled. I mean, they just don't exist!"
"Apparently," Grindelwald said, tilting his head, "they've been growing, I found them entrenched—a parasite within a parasite. They didn't disappear, Tony. They adapted."
Tony snapped the folder shut and looked up. "You're telling me they're inside SHIELD?"
"Not just inside," Grindelwald replied, folding his hands. "They've become part of the spine. Integrated. Hidden. Some of my people captured an informant—I expected a rogue SHIELD agent or black-market fence. Instead, we uncovered something much more… insidious."
Tony rubbed his face with both hands. "This is insane. Are you absolutely sure?"
Grindelwald rose from the chair, his movements deliberate, his voice low.
"I have names. A list. Operations. Funding routes. Even the safe houses." He walked to his desk and retrieved a second file. "This is just a fragment. But enough to begin an uprooting."
Tony took it, flipping through the names. He stopped dead at one familiar codename.
"Oh, hell… that's a SHIELD deputy director," he whispered. "This isn't small…"
"No," Grindelwald agreed. "It never was."
There was a pause between them—just long enough for the weight of it all to settle. Then Grindelwald casually leaned against the desk and added "I'd like to do something about it. With your permission, of course."
Tony narrowed his eyes. "…What kind of something?"
The wizard offered a faint, too-pleasant smile. "Let's call it... management restructuring."
Tony stared.
"Grindelwald."
"Yes?"
"Don't dance around it. What do you mean?"
Grindlewald gave a dramatic sigh, clearly disappointed he had to spell it out.
"Fine. I'd like to use a bit of mind control. Nothing extreme—just a light… persuasion. I assure you, my methods are quite refined."
Tony gawked. "Are you out of your wizarding mind?! You want me to let you brainwash SHIELD and Hydra agents like some dark overlord consultant?!"
Grindelwald looked mildly offended. "You make it sound so crude. I'm not talking about Imperius Curses or torture. Merely… enhancing their alignment. Redirecting their loyalty. Conditioning, if you will. Much like your own government does—just more efficiently."
Tony paced across the room. "You're suggesting we fight brainwashing with more brainwashing. That doesn't fix anything—it just changes who's holding the leash."
"And would you rather let these snakes remain hidden and slithering through your so-called security agency?" Grindelwald said, voice sharpening slightly. "If you play by your rules, you'll never get them out before they strangle what's left of SHIELD."
Tony stopped walking. "You want a blank check to manipulate people's minds. And you came to me for permission."
"You are, after all, the king" Grindelwald said with a grin. "And I believe in respecting domains."
Tony looked down at the file, then back at Grindelwald. "If I even consider this… if… I need oversight. Control. And no hurting anyone."
Grindelwald bowed mockingly. "I'm wounded, Tony. Do I look like a villain?"
Tony gave him a look.
Grindelwald laughed.