Warning: Rules are broken here, tread lightly

It was just another normal day within the confines of Fuyuki City. At least, it was for the average citizen. Though for an individual among them, days like these were very few and far between. Days where he wouldn't attract any attention whatsoever. Where he could be just another tiny spec in this vast universe he lived in. Of course, 'the other guy'would still be in there- in him somewhere. But it was still nice to at least pretend he was a normal person.

The individual in question? Doctor Bruce Banner, or should he say former doctor? Really, it's been so long since he'd been able to use his actual skills to good use, he's basically a nomad now. Complete with an unkept beard and disheveled clothing he got off the back of several dumpsters and also shoplifting from a couple of stores.

"Well, it's not much. But it's something at least" He thought, looking at the small amount of money he managed to scrounge up from both the streets themselves and random civilians' pockets. He definitely would not be able to find a place to stay, but he would be able to purchase some food, meager as it would be.

Unfortunately for him, he was too busy thinking to himself while he was in the middle of the street. That he hadn't noticed the hastily tied laces of his shoes come apart. He tripped, causing his body to crash into two other people, their bags falling to the ground as they went down with him.

Immediately after said collision, he quickly got himself up, tied his shoes and tried to help the two people he crashed into with their belongings, which they accepted, he didn't want to make too much of a commotion. He took note of their clothes, uniforms, school uniforms to be exact. One boy was a redhead acompanied with a pair of golden eyes, with most of his uniform being unbuttoned, the other boy was wearing glasses and Bruce was thankful at the fact they hadn't been broken in the crash or else he might have been in a lot more of a debacle than he could handle right now.

"Are you two kids alright?" He had asked as best as he could, his Japanese was still rough though, he planned to improve on that.

"We're both fine sir, just a little surprised is all" The readhead calmly spoke. His bespecticled companion only giving a curt nod as a sign of confirmation.

"Heh… sorry about that, I was sort of lost in my own head there" He Apologized. "Anyways… I suppose I'll be going now" He quickly went passed the two teens. Walking at a brisk pace, getting out of the two's line of sight.

"Well, that went alright" He thought, before realizing… "Goddamnit! Should've asked them for directions to the nearest library!" He slapped his hand against his forehead. Though he quickly calmed down, and resumed his walk around the city.

Homurahara Academy

"That man…he felt…"

"Are you alright Emiya?" Issei asked, cutting him off from his thoughts

"..Yeah, im fine" He responded as the both of them continued their walk into Homurahara Academy, his mind still lingering towards their little accident near the front gates of the school. Still lingering to thoughts of the stranger that had crashed into him and Issei. Emiya Shirou was one who stood foot in the moonlit world, a novice in the ways of magi who experienced even less than the bare minimum of training from his adoptive father and had to make do on his own.

But even someone like him could feel the pressure in the air when he went near that man.

Fuyuki City Church

A blond man sat inside a church, a priest standing near him. Noticing the calm look on his face turn into a slight frown.

"Is there something that bothers you, my king?" The priest politely asked.

"...Think nothing of it, Kotomine." He said with a sense of finality. His thoughts elsewhere.

"That abomination is here, passing through my kingdom's gates once again" He thought, he never thought he'd get to encounter it again. Not after his and Enkidu's run-in with it in his first life.

"And yet…"

Yet it also felt weaker, restrained. As if it was only partially in this realm. Like a stream of water being released through a mere household faucet instead of the tsunami he had felt back then.

"Hmm…"

Hours later…

It was night-time when Bruce was walking near what he assumed was the city church on the outskirts of Fuyuki, starting to get tired as he had spent the day moving around most of the city simply exploring, while also asking for directions towards the public library.

"Feels… refreshing" He thought to himself, commenting on the lack of noise around him save a few small animals. "Well, guess I'll hit the hay near the-"

BOOOMMMM

His thoughts were cut short when a loud Boom reached his ears, covering his ears on reflex. Bruce looked towards the direction he heard it come from.

It came from around the church, probably from area of the park near it.

CLANG

Another sound reached his ears, this time the clashing of weapons.

He sighed, "Well, so much for peace and quite"

And with that, Bruce's legs moved towards the direction of the battle. As the sound of another explosion reached his ears as he got closer.

As he reached the source of the noise. He saw the three that were standing in the sidelines.

One was a girl with pig-tails and blue eyes, sporting a red coat around her body. The other was seemingly a little girl with white hair and red eyes, standing far away, opposite the other two. The third one, had a familiar mop of red hair, wearing a black and white jacket in place of the school uniform he had seen earlier today.

"The Kid? Why is he here?"

But then he saw the two of them that were fighting against each other, one was blond, covered in blue and silver armor. Holding up something he couldn't see clearly near their chest though it was most definitely a weapon. The Knight was saying something. But Bruces' mind was a lot more focused on the other figure.

"No…No it can't be… How the hell?!" He mentally shouted.

Whereas one could pass as a normal person, the other was a colossus. A dark-skinned muscular beast of a man with bone-like structures jutting of it's elbows. Clad in arm and leg braces with a metal-plated skirt around his waist, wielding a sharp jagged rock in one hand.

Bruce's mind raced as he could feel the sweat roll of his chin, another one like him here in Japan?! How the hell did he not know about this?!

He could feel the other guy start pounding inside his head, should he?! He didn't know enough about the situation! He could be making a mi-

His thoughts and reservations were cut short as he saw the behemoth's skin start to emit smoke and glow a dark red. It's body preparing to launch itself in the general direction of the knight and the teens.

"Alright, I'll tag out. But only for now, you hear?"

"…Fine."

As the now steaming red warrior barreled towards the knight, his eyes flashed green.

And as the jagged edge of the rock moved to strike the metal armor of the knight. It found itself being caught by flesh instead.

Fuyuki City Church

"!"

He felt it, it's presence was stronger, still a far cry from what it had been before. But now it's restraints were lessened, more of it unleashed onto the world.

"It seems your strength isn't entirely gone, abomination" The golden king observed.

"I suppose this war will be much more interesting than I had previously thought it'd be" He thought with a small smirk on his face. Unnoticed by the priest.

The battlefield

Every one of their eyes widened in shock. Even the warrior's eyes seemed to widen in surprised at this newcomer.

It was no normal man.

It was a goliath on-par with himself in terms of size. With short black hair, and abnormal green eyes. Bearing equally green skin littered with veins and muscles that pulsed underneath the surface of it. The expression on it's face could only be described somewhere between a snarl and a manic grin. Before letting out an inhuman yell of rage.

RRRAAAAAAGGHHHH!

As his weapon dug into the flesh of its hands. He felt said weapon being forcibly pulled forward, before then getting his face struck by a massive green fist almost twice the size of an average adult's head. Sending him flying back across the field.

"Sorry for popping in uninvited," he spoke in broken Japanese, his head rotating back to look at the knight, a frown visible on his face. "But hope you don't mind the help" his stated, before flicking his eyes towards the direction of the three children standing on the sidelines watching the fight. And yelling "You three better get away before you get hurt!" Before crouching down and preparing to lunge at the still recovering warrior.

"Wai-" The knight attempted to speak, though said attempt failed as the green goliath had already jumped away, tackling the warrior back on the ground. Gripping his arms onto the warriors body, before pulling back his right arm and sending it smashing down onto his chest. And then repeating the motion by pulling back on his left arm and bringing it down on the warriors chest again. Before pulling both arms above his head, and with a yell brought down both his fists simultaneously upon the downed colossus.

Though before the onslaught of attacks could continue, the grey giant managed to recover and grabbed onto one of the green goliath's arms before flinging him back next to the knight who still stood in shock over the goliath's arrival.

The Green giant quickly recovered, before looking towards the knight. "Hey! You helping or not?!" He questioned, there was a short period of silence between the two as they simply looked at the other. The blond's mind seemingly elsewhere. Then the knight looked towards the redhead still watching the fight as their eyes locked with his, nodding their head, before turning back to him and stating. "Alright, though i do not know you. My master seems to have placed his trust upon you, as such I'll accept your assistance in this battle" The knight then readied themselves against the warrior.

"Master?" Banner questioned, ignoring him for now. The green goliath readied himself beside the knight. Both staring down the grey giant across the battlefield.

With Saber

Unknown to the both of them. A silent yet quick conversation occurred between Saber and the teen. Yet even after being convinced by Shirou. The knight still had lingering questions of her own regarding the stranger.

"The green skin, the size... And the one that Sir Gawain-" That thought was cut short as she blocked another strike from Berserker. That would have to be saved for later as even the hindered force of Berserker's attack managed to fling her back towards Shirou and Rin

"Saber, did you do it?"She heard her master ask behind her, with Rin behind him looking quite stressed

"Yes, I and our guest here have agreed to form a truce, for now at least" She said as she looked towards the battle, observing as the green stranger fought and kept Berserker busy. His fist striking the mad warriors chest as his other arm had grabbed hold of Berserker's sword arm.

"Alright…Thanks, by the way. For trusting me, I know it's risky since we don't-" She cut him off before he could finish.

"No need for thanks, Shirou." She stated before going back into the fight.

"Still, thank you Saber" Her master said as she left, and a small smile managed to form on her face even as she rejoined battle. With shots fired of from Archer nearing their location.

Near the fight, moments after

"I can't believe I'm even agreeing to this idea" She said in disbelief, bringing both her hands to her face.

"I know it was a risk to have Saber fight with him, Tohsaka. But I don't think he's here to hurt us" He said standing beside her.

Her head snapped towards him "And how would you know?! You said so yourself that the single interaction you've had with him is that you might have met him on the streets earlier today!" She shouted. "Besides, even if he did yell at us to get to safety. That doesn't necessarily make him a non-threat"

"Maybe so, but if he really was here to fight us wouldn't he have attacked us directly instead of defending Saber from Berserker?" He argued back.

As the both of them were having this conversation, both had noticed that the young girl dressed in purple- the Einzbern master of Berserker hadn't said a word since the green stranger's arrival. She hadn't even made a move against the two of them. Simply watching the battle as they have with her eyes focused on the green giant.

Soon enough, as the battle continued through the night. It had moved towards the forest, nearing the old graveyard. The Einzbern master trailing close behind, with Rin, and eventually Shirou following suit.

Meanwhile, several Kilometers away, atop one of the city's buildings

The Archer in red drew back his bow once more, preparing another volley of his arrows to launch at the Berserker. Releasing them as they shot out and flew through the air like miniature rockets. A single thought playing through his head more than any other.

"This definitely happened differently back then…"

Sighing, he decided to try something different.

"Master, I suggest you move yourself and the idiot and leave the area" He called on her, as he prepared a different type of arrow with his hand. One with a spiral shaped blade as it's base.

At that same time

He felt pain as the serated edge of the other giants rock dug into his body, he felt pain when his arms were grabbed and he was flung into the trees surrounding them, he felt pain when his head was stomped on by a massive foot repeatedly before being stopped by the knight in blue.

Yet this pain would only serve make him angrier. And with anger, came strength.

He launched himself at the enemy in front of him, distracted by the knight. Grabbing onto his left arm before pulling his body above himself and slamming it down on the ground.

Then he started to use both of his arms to twist and pull at the arm he was holding, putting his left foot down on the head, smiling at the sight of the grey skin starting to rip apart. This didn't go on for long as the knight took this opportunity to charge in, the air around the weapon in her hands beginning to warp and gather as it pierced through and destroyed a chunk of the body. His arm completely severed as the green goliath was still pulling on it.

As her blade ripped through flesh, he could see what looks to be a sword shine brightly in the knight arms, though only for a moment as it turned back into it's previous form with the air covering it's form in front of his eyes.

With the both of them backing away from the downed combatant, they could see the glowing red eyes quickly turning a dull grey. "Heh, guess that does it" He spoke, throwing away the arm he was still holding, "Yeah, though…" Banner spoke, confused by how this felt too easy and too quick. If this man was another similar to himself. Something like this would not have stopped him, as even worse things would definitely still not stop the other guy, he knew from experience.

The green goliath simply continued smirking at the sight, before noticing on the edge of his line of sight a mop of orange hair moving towards them, shouting "SABER!". "Guess that's her name then" Banner said, he simply nodded in aggrement.

Before he could reach the both of them, the knight shouted back at the boy.

"STAY BACK SHIROU, DON'T COME NEAR US!" Surprised by this, he looked back to the knight and saw how Saber's eyes was still focused on the downed enemy, turning his head towards the direction of the corpse.

Or rather, the regenerating body.

"I hate being right sometimes" Banner spoke.

"A Noble Phantasm that activates at the moment of death" He heard Saber say as she prepared herself and raised her cloaked blade. "Noble Phantasm?, guess we'll ask about that later" Banner spoke inside their head.

Before he could throw himself at the still regenerating enemy, he saw the boy- Shirou grab Saber's hand as he moved her and himself away from the fight. Shouting "GET OUT OF HERE!" at him as he did so.

Hesitating for a moment, he suddenly saw a bright light cover the area around him and his opponent. Before looking up towards the sky, eyes widening as he could see something rocketing towards his vicinity, different from the previous volleys of projectiles he'd been seeing previously in the fight.

He knew he didn't have enough time to get away, and so the only thing he did before impact was uttering a single word from his mouth.

"Damnit"

BBBOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMMMMMMMMMMM!

?

Everything hurt like hell.

His entire being felt like hell. And everything around him was dark.

He couldn't even tell if his eyes were shut or if they were just vaporized in the blast. Though he couldn't even be bothered to care. The only thing on his mind being the pain. And the state of the three kids he saw near the fight.

Though eventually something broke the darkness in front of his eyes.

A green door.

He heard the sound of metal footsteps before he felt a hand clasp his shoulder-

!

His eyes shot open, seeing the broken ground beneath him.

Ah, he was faced flat down on the dirt. Moving the palms of his hands to the sides of his body, he pushed his himself back up, making sure to survey the area for the kids. Though his head was still in severe pain. Touching his head, he felt pain as he realized that a large part of it was now merely muscle and bone. No matter, that'll fix itself soon.

He realized the young girl with the white hair wasn't here, the other Behemoth seems to have disappeared as well. He looked around until he saw Saber holding a downed Shirou, the other girl was standing near them before helping Saber with the injured boy. He approached them, before seeing the twin-tailed girl hold out one arm towards his direction with the other holding it, seemingly like she was prepared to fire something out of her hand.

He held his large hands in a surrender position. Before stating "I'm not here to fight, I'm here to help, seem's like you could use some" Pointing at the Boy. The girl was still hesitant. The boy saw this, and even while half conscious, managed to get a word in

"I-it's alright, Tohsaka. Let him help" He pleaded. The girl sighed, lowering her arm, though still focused her eyes on the green giant.

"It's okay-" He stopped short, before sighing "Well, seems like I won't be here for much longer, Banner's taking back the driver's seat now" He closed his eyes.

"Huh?" Tohsaka and Saber where confused, though their confusion grew a hundredfold as the Green giant in front of them slowly shrunk into the size of an average man, albeit still with ripped purple pants.

Their eyes widened as their jaws dropped. Yet in comparison Shirou was calm, smilling even. Though that might have been the blood loss. Banner noticed this.

"How did you know?" He asked as he approached and held up the redhead along with Saber.

"I saw- no, it'd be more accurate to say that I felt you come near us when Saber was still fighting Berserker, the same feeling as when we crashed into eachother, just stronger, a lot stronger" He stopped to cough before continuing. "After you defended Saber from Berserker, well i-"

"That, would be the other guy" He cut him off, confusing the the trio as they looked him with raised eyebrows.

"I'll explain it in full later, after we get you to a hospital or something" He assured, looking at the teen's wounds.

"No, we're heading straight to his home, it'll be more private that way"

"…Alright, but you won't be the only one getting answers, i still don't know what the hell is going on here" He responded

"Deal" She said with a small smirk.

Next day

!

Shirou woke up in surprise. Seeing no one else in the room with him, he decided to get dressed despite his bandaged wounds.

"What was that?" He thought, mind still lingering on the landscape of swords he saw while recovering

He opened the door to the main room, seeing three people sitting down on the table.

Saber, a white shirt with a blue tie and a blue skirt that went down to her knee.

Rin, still wearing the same clothes she did last night.

The stranger, now clean-shaven, wearing all black. Probably taken from Kiritsugu's wardrobe, or at least what was left.

He sat down beside Saber, as his eyes looked towards the strangers.

He sighed, before speaking "The two of them already explained this whole Grail War deal to me. And while this stuff isn't in my usual ballpark, I still feel like I should help. Now moving on from that.." He paused. Before continuing. A hand pressed against his chest.

"Alright, let's get to the basics. My name is Bruce Banner, and the big green giant you saw fight? Well, I usually call him the other guy, but his name, is The Hulk"

Alright, longest one yet. This one was actually one of the earlier ideas that popped in my head. The aspects from Immortal Hulk and The Green Knight were actually recent additions, though Gilgamesh having a past with our jolly green giant was actually inspired from Avengers 1000 B.C, it was Originally supposed to be the original Star-Brand of this universe, but I changed it to The one Below All since that would tie-in to Hulk a lot easier.

Another thing is that making this made me realize how much I forgot about the earlier events of Stay Night.

Anyone prepared for the summer banner, I certainly am (Not).