"Morning Izuku!" Ochako shouts as she stumbles into the kitchen on a crisp morning.
"Morning Ochako." Izuku replies.
"You want to go to Momo's today? she says she has a surprise for us." Ochako asks as she accepts a bowl of rice from Izuku.
"Sounds fun. Can I bring Eri? Mr. Aizawa has basically left her to me since the Ferdinand incident." Izuku says as he serves himself.
"Of course, she says the surprise is related to the new aspect of your quirk." Ochako answers.
"You mean how he can 'take over' any tank with his quirk?" Tsu asks as she sits down with her breakfast.
"Yes that one, I really need to return to that museum and apologize again." Izuku says.
"They were fine with it, you only broke a few signs and it's not the worst damage a quirk has done." Tsu says.
"Still, I'll volunteer at their next event as penance." Izuku says firmly.
"Is that really a punishment?" Ochako asks accusingly.
"Eh, not really." Izuku says, "but at least I'm doing something for them."
"Anyway, let's get eating, I want to get to Momo's soon." Ochako says.
"Alright, let's see what I get. We can take the train if it's not fast enough." Izuku says cautiously as he stands outside UA's entrance.
"I still haven't seen you get unlucky outside of class and emergencies." Tsu says.
"Don't remind me." Izuku groans before raising his hands into the air.
"Well, that will do." Tsu says.
"Oh! It's cute!" Ochako cheers, as she admires the small tank with a rather large turret and stubby gun.
"Indeed, a light tank turned into an assault gun is rather endearing." Izuku comments.
"Let's just get in." Tsu says before jumping onto the turret.
"Izu, tell me about the tank." Eri asks as she sits on Izuku's lap in the commander's position.
"Well, it's called the BT-42, a Finnish conversion of the BT-7 light tank." Izuku begins before remembering his audience. "It's a special version of another tank to hold a bigger gun."
"How big?" Eri asks.
"114 mm" Izuku answers, using his hands to show the approximate size.
"Whoa." Eri responds.
Before Izuku can continue on an impromptu history lecture Ochako hands him two leather helmets and goggles and not so subtly urges him to get going.
With a bang and a disturbingly large cloud of black smoke from the exhaust the overweight light tank races off at high speed. Speed limits were ignored as Izuku simply explained, "We're in a tank." when asked about it. Eri was of course having a great time with her oversized helmet and goggles, giggling all the way as the tank weaves through terrified traffic and slides dangerously around corners.
After a far too short half hour drive they arrive at Momo's UA residence, that had been converted into a tank hall once she had moved into the dorms. Upon seeing the new tank Momo sent them straight to the full sized 3D scanner she had bought as soon as she learned Izuku had a license to drive tanks on public roads.
"This one's unique!" Momo cheers, "I'm adding it to my collection as soon as I can!"
"Make sure you eat well tonight then." Izuku replies as he gently lifts Eri out of the tank.
"I will!" Momo replies as she activates the scanner and proceeds to lead them though the garage to a massive wooden box. "I finished these last weekend." She explains, "both use special washable paint rounds so we can fight to our hearts content."
"Let's see them then." Tsu says.
With a flourish Momo triggers the small explosives on the top of the box and the front falls down, revealing two massive KV-2's in red and blue paint jobs.
"Nice." Izuku says.
"KV-2? Really? Isn't that the largest gun Izuku has created so far?" Tsu asks.
"I like big guns." Momo replies nervously.
"I love cannons too!" Ochako agrees.
"Let's get started, I assume it's going to be Eri and me vs your three?" Izuku says enthusiastically.
"Yes, I've given the red one a loading elevator so we should be able to handle it with just the three of us." Momo explains.
"I'm driving." Tsu says.
"I'll take the gun." Ochako adds quickly.
"Great, I have to command and load." Momo sighs.
Getting into the tanks immediately reveals them as Momo replicas as they are covered in padding and other creature comforts no WW2 era vehicle would even consider.
"Where do you want to sit, Eri?" Izuku asks as he carries her though the hatch.
"Loader seat." Eri says happily.
"Perfect, now what do you know about the KV-2?" Izuku asks.
"Strong tank." Eri replies with a giggle.
"Yes Eri, Strong tank!" Izuku shouts.
"Strong Tank!" Eri repeats.
It was a glorious day, the two KV-2s fought for hours in the small arena Momo had her gardeners create. Izuku's instinctive control and experience pitted against the three girl's teamwork and strategy. When the day finally ended and the tanks were parked the score was Izuku and Eri 17, Momo, Ochako and Tsu 6.
"I still don't know how you got a tank up there." Momo wonders as they return to the BT-42.
"Just rock the tank with the turret and it can slide sideways." Izuku explains.
"No amount of teamwork can coordinate that." Ochako pouts.
"You guys still got me a few times though." Izuku says, "that red paint job is surprisingly stealthy when the field is covered in missed shots."
"Maybe you should aim better." Tsu says.
"I aim fine." Izuku replies haughtily, "I just like to fire my gun as much as possible."
"Sure." Tsu says.
"Ochako hit over half the shots she fired." Momo says.
"Yeah, but did that win matches? How many times did I win because I got the shot off first?" Izuku asks.
"You also lost two rounds because you missed." Ochako counters.
"A fair trade." Izuku returns confidently.
"I'm hungry." Eri complains, ending the argument as they scramble to get into the BT-42 and back to UA for a big meal.
"I have just the thing for the return trip." Momo says as she settles into an alcove behind the gunner's seat.
"There's not enough space for cushions." Ochako says as she squeezes into the gunner/loaders seat.
"No, I have an instrument." Momo declares as she creates a kantele and begins playing it as Izuku pulls out of the garage.
"Oh no." Tsu says with resignation as the music stirs Izuku to even greater speed and recklessness.
Aizawa calmly walked to the gate as he mentally prepared for his evening patrol. It had been a relaxing day as the problem children had gone out. Of course this ended as a tank, that could only belong to one person, flew through the gate on only one set of tracks, music blaring and massive smiles on the visible occupants.
"I'm going to have to clean up after that aren't I." Aizawa mutters.
"You mean the tank that just entered playing Säkkijärven Polkka?" Present Mic asks from the gate.
"Do you see any other problem right now?" Aizawa asks menacingly.
'I'm not going to mention Hatsume's latest accident then.' Present Mic thinks as Aizawa stalks past.
AN: I felt like writing something casual instead of plot focused, and this is the result. I'm sort of recharging my creative juices so who knows what I'll write next, maybe I-island or a quick first day at camp; It's all up in the air. Anyway, thanks for the tank suggestions, even if I don't write about them in a hurry they grow into ideas over time. Jlargent suggested the BT-42 and inspired part of this chapter for example, On the other hand I still haven't thought of anything for the Praying Mantis, no matter how wonderful it is.
In other news, I'm keeping this quirks abilities vague for obvious reasons, he probably can't summon tank girls, no matter how interesting it would be if he summoned a girl with a sign reading 'tank.' One for All is not really a thing in this story, since it makes things too serious, not that I won't make a sidestory with it...
P.S. If I may clarify the characterization a bit here in the edit, Izuku is a real nerd for historical tanks, Ochako just likes the cannons, Momo has gone down the deep end and is a full on tank geek, and Tsu was roped into this ages ago and is too polite to leave.