The Cube Experimental Base, Arizona Desert.
In this reality, because a young man named Rick Jones had never trespassed onto the testing grounds as a delinquent "ghost rider" youth, Bruce Banner had never been harmed. That was, until this very moment, when a flaming skull riding a hellfire motorcycle crashed into the experimental base, carving a path through the military's heavy fire all the way into the research building.
"Dammit, stop him! Where are the Avengers? Where are the Avengers!"
General Ross, the man in charge of the Cube Base, roared in fury. However, those around him were at a loss, paralyzed by indecision. Accompanying his roar was the maniacal laughter of the Ghost Rider as he charged into the testing arena. Here, several newly created Gamma Soldiers were unleashed to deal with the Rider.
Or rather, they thought they could deal with him.
A burly Gamma Soldier slammed a fist into the Ghost Rider's head, but the Rider merely let his head tilt instinctively with the impact. Then, he turned to face his attacker. Within his eye sockets burned swirling vortices of fire as he pronounced judgment.
"Your soul is stained with the blood of the innocent. Face penance."
As the Gamma Soldier's eyes were scorched by hellfire, he collapsed to the ground. The Ghost Rider tore through the ranks of the remaining Gamma Soldiers as if they were nothing, searching for Bruce Banner. Banner, completely unaware that he was the target, was following standard evacuation procedures when a wall was suddenly burned through. A skeleton clad in a spiked leather jacket, wreathed in hellfire and wrapped in chains, stepped out from the smoke.
"My God... I'm going to have to start going to church."
As Banner spoke, he grabbed his bag and fled. Ignoring the soldiers' rifle fire, the Ghost Rider used his burning chains to melt their weapons instantly. He then hooked the chain around Banner's leg, dragging him back. Hoisting Banner up by the collar, the Rider looked deep into his eyes.
"Face penance, Bruce Banner. Embrace your true soul."
Hellfire burned within Banner's eyes. He saw himself being struck by a massive dose of Gamma radiation to save a young man named Rick Jones, becoming the Hulk. He saw the Hulk's battles against the Hulkbuster units as a monster; he saw the great clash with Blonsky in Brooklyn; he saw the Battle of New York and the Avengers.
These were events that had never happened in this timeline, yet they now surfaced within Banner's memory.
The burning continued, but the judgment had ended. With a mixture of confusion and a touch of poignancy, the Ghost Rider spoke: "You have hurt many, but your soul is kind. Your repentance is sincere; your guilt is light..."
Without warning, a massive green fist smashed into the Ghost Rider's flaming head, sending him flying. Banner, teeth gritted and muscles bulging, let out a pained roar as he transformed into the giant green monster.
The Ghost Rider climbed out of the rubble. He was immune to physical damage, but that didn't mean he was immune to physical force; if he was hit, he still went flying.
What the hell is Mephisto doing? Didn't he say he'd only awaken the soul? How did the reality altered by the Cosmic Cube get restored along with it?!
Oh, right. He only mentioned awakening the soul. He didn't say anything about other effects. Technically, he didn't lie.
The Ghost Rider stood up. Seeing the Hulk charging toward him, he gave a shout of glee and swung his chain at the Hulk. Like a cowboy roping cattle, he lashed the chain firmly around the Hulk's neck and gave a violent yank.
He didn't budge him.
The Ghost Rider stared at the Hulk for a few seconds. He watched the Hulk grit his teeth and pull at the chain locked around his throat, seemingly perplexed as to why he couldn't break the links. Instead, the Hulk chose to grab the chain and slam the Ghost Rider into the ground on one side, then the other, swinging him back and forth several times before finally smashing him into the floor like a flail.
The Ghost Rider seized his moment, planting his feet firmly on the ground. Hellfire raced down the chain, engulfing the Hulk's body. The Hulk let out a cry of agony under the searing heat, yet he struggled to grip the chain, pulling it toward himself inch by inch. He dragged the Ghost Rider right to his face and delivered a massive, bone-shaking headbutt.
The Ghost Rider looked at the Hulk and asked in a flat, puzzled tone.
"Are you sure you want to keep doing this? It's quite useless."
The response was a roar from the Hulk. It wasn't clear if it was the pressure of the roar or the Hulk's spit, but it nearly extinguished the fire on the Ghost Rider's head. In retaliation, the Rider delivered a headbutt of his own, setting the Hulk's head on fire. Whether it caused any real damage was unknown, but the Hulk's hair was likely a lost cause.
The Hulk stepped back two paces, having achieved his goal. His neck was no longer constricted, allowing him to breathe freely. He stomped heavily toward the Ghost Rider; as the ground cracked open, the Rider fell into a fissure and got stuck.
At that moment, the sound of clapping rang out. Mephisto appeared, looking at the two combatants with a smile before turning to the Hulk: "Hulk, Bruce Banner... originally two sides of one person, yet through a series of circumstances, you have gradually become two distinct individuals. Quite rare. I have a proposal you might find acceptable."
"I can help you restore the entire world, and the price is negligible. You have two souls; give one of them to me. The other can possess both bodies simultaneously but with only one consciousness. What do you say?"
"So, this was your goal all along."
The Ghost Rider, climbing out of the fissure, suddenly spoke. He looked at Mephisto and lashed out with his chain. Mephisto caught the chain effortlessly, raising an eyebrow: "You wouldn't be this stupid, would you, Johnny?"
"Of course not. I met two new friends on the way, Mephisto." The Ghost Rider let out a raspy, cackling laugh. At the same time, the chain in his hand began to spin rapidly, the hellfire forming a burning arc in mid-air. "They taught me a few new tricks."
The arc suddenly tore open into a portal. Strange stepped through, followed by Peter and Logan, standing before Mephisto. Strange had rested well and regained his strength; ensuring he was at the top of his game, he offered Mephisto a smile: "Mephistopheles. Our first meeting. A pleasure."
"Might I ask you to kindly go back to Hell?"
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(Fun fact: Ghost Rider isn't actually immune to physical damage; rather, the immortality and ultra-fast regeneration granted by hellfire make him appear as if he is. Compared to other characters with healing factors, the main difference is the addition of immortality.)