'Iida!' Izuku thinks as he rushes down the streets of Hosu city. 'I need to get there fast and I need firepower. Come on quirk, don't fail me now!'
"Aw! come on! Of all things I could have summoned!" Izuku shouts at a large box of corrugated iron that stood before him menacingly.
Izuku didn't let his disappointment stop him, even if his tank was slower than walking. He was happy it was at least small enough to actually fit down an ally. 'I could have summoned an M1 or something and then I would be truly done for.' he thinks as his tank lurches forward.
Just as Stain was about to finish off Iida, the clatter of tracks that had been growing for some time reached a crescendo as what looked like a rolling shanty town came around the corner and lumbered towards them.
"Is that a new garbage collection robot?" Stain wonders before his thoughts are interrupted by a hail of gunfire from three .303 machine guns forced him back and away from the fallen heroes.
"Iida!" Izuku shouts as he exits his tank.
"Midoriya! What are you doing here!?" Iida shouts angrily as he struggles against Stain's quirk.
"Saving you! And Native..." Izuku shouts as his machineguns continue their barrage of rubber.
"Leave me! I must kill Stain!" Iida protests.
Izuku proceeded to make the best possible decision at that moment and knocked Iida unconscious with a well aimed chop to the back of his head. He then roughly tossed Iida's body into his tank. Izuku quickly moves Native into the tank as well, but just as he closes the hatch he hears a loud clang as Stain stabs one of the front Bren guns, putting it out of action.
"Get off!" Izuku shouts as he grabs one of the useless side guns and sprays it out of the forward firing port.
"Those are my prey! No kid in a box is taking them from me!" Stain shouts passionately.
"This is no mere box! This is a Bob Semple tank! A true symbol of Kiwi fighting spirit!" Izuku replies angrily as even a bad tank deserves respect.
"If that's a tank, then I'm a hero!" Stain taunts.
"If we Japanese had invaded New Zealand back in world war two, countless of our soldiers would have been cut down by this feat of pure determination!" Izuku shouts.
"Someone... actually made that... for a war." Stain manages between bursts of laughter.
"Are you insulting the late honourable Bob Semple!?" Izuku shouts.
"And what if I am!" Stain replies, truly distracted from his original mission.
"If he was alive I'd dare you to say it to his face! Even as a pre-quirk gentleman, you wouldn't stand a chance against an angry Australian turned New Zealander!" Izuku shouts.
"Some pre-quirk Zealander wouldn't intimidate me!" Stain shouts.
"Those are fighting words for someone standing in range of Fighting Bob Semple's tank!" Izuku shouts.
Stain was truly offended by these words and replied with only an incoherent shout of rage as he rushed the corrugated iron combat vehicle. His rush was met by a renewed torrent of machine gun fire as Izuku had used the shouting match as an opportunity to replace the broken machine gun.
As Stain reached sword range of the tank, Izuku threw open the drivers view port and added to the considerable rain of rubber by hip firing another Bren, forcing Stain back as even he couldn't handle four machine guns worth of fire.
While all this was happening, the quite considerable cacophony of gunfire had not been unnoticed by nearby heroes, as not even nomus make more noise than several machine guns in an alley. A sidekick was sent to investigate, and as soon as she noticed Stain, she radioed her hero and reinforcements were sent to the scene.
Gran Torino offered to deal with it, as the report of gunfire could only mean one person. And he was correct as he raced around a corner only to run into a wall of sound as Izuku had not ceased his endless assault. Gran Torino quickly remembered what Izuku had told him earlier when he asked about him running out of ammo:
"Kid, you need to get better at fighting soon, or one day you'll be in trouble when you run out of ammo in your tanks!" Gran Torino instructs as he easily runs rings around Izuku.
"I won't run out of ammo." Izuku says, suddenly serious.
"It's a real concern." Gran Torino says, carefully observing Izuku's change in demeanor.
"I have bullets for days." Izuku says darkly.
"Bullets for days?" Gran Torino asks.
"Bullets ... for ... Days." Izuku says.
'Guess the kid was right." Gran Torino thinks as he jumps over the retreating tank.
"Izuku, get out of here. This one's mine." Gran Torino orders as he quickly disarms and disorients Stain.
What followed was a textbook example of why speed paired with experience is simply unbeatable without overwhelming power or defense. Stain looks like a child lashing out at his tormentors as Gran Torino efficiently knocks weapons out of his hands and disables limbs with precise kicks at pressure points.
'He was really toning it down for me...' Izuku thinks as he observes the one-sided beat down. 'As expected for the man who trained All Might.'
And like that Stain was defeated. Once Gran Torino moved away to rest on Izuku's tank, Izuku took the opportunity to fire a few rubber bullets into the handcuffed villain. This earned him a kick courtesy of Gran Torino.
"Heroes don't hurt people out of spite!" Gran Torino shouts.
"Yes Sir, but he damaged Bob Semple, and insulted it and it's creator." Izuku complains.
"Doesn't matter! Don't do it again!" Gran Torino instructs as the tank finally reaches the streets and Izuku climbs out of the driver's viewport.
The police and remaining heroes began converging on the area, the lumbering monstrosity of a tank proving to be an excellent landmark. As the police begin dragging Stain out of the alleyway a nomu sweeps down and grabs Izuku.
"I'm never leaving my tanks again." Izuku thinks as he begins aiming his machine guns.
"Kid!" Gran Torino shouts, but Izuku is out of range before he could move.
As the heroes panic a burst of machine gun fire erupts from Bob's turret, striking the nomu's limbs and forcing it to drop Izuku. As soon as it notices its cargo was dropped the nomu turns to grab Izuku again, but the forward machine guns on Bob open fire with real bullets, tearing holes into the nomu and killing it before Izuku is caught by Gran Torino.
"I think that's enough for one day." Izuku groans as he is placed on the ground.
"You did alright kid." Gran Torino says as Izuku loses consciousness.
'Maybe all those bullets sapped his energy?' Gran Torino thinks, 'I'll have to ask him later.'
AN: Of all the tanks suggested, Bob Semple just worked well here, as it's both useless and useful at the same time. I believe 7 people requested this tank, and as an enthusiast I was always going to use it. Though the review suggesting the Maus, but summoned the wrong way was tempting. Might use the wrong way idea later, it has a lot of merit with the amount of close quarter environments we see in fights.
I honestly don't have a hero name for Izuku, I might just not mention it as it's not that important... Also, Izuku's weakness (other than bad luck) using too much ammo drains his stamina, just an idea for now, and I won't make it a big deal, but such a weakness could prevent some truly unfair exploits.