The air crackled, thick with the ozone scent of godly ki. The ruined cityscape of the future was a grim canvas for their battle. Goku Black, his hair a brilliant, shimmering Rosé, breathed heavily, a thin trail of blood tracing a path from his lip. Across from him, Goku and Vegeta stood united, their auras blazing like twin cerulean suns in their Super Saiyan Blue forms.

"It's over, impostor!" Vegeta snarled, his fists clenched so tight his knuckles were white. "Your borrowed power is nothing compared to the strength we've forged ourselves!"

"You're fighting for just yourself" Goku added, his usual cheer replaced by grim determination. "That's why you're gonna lose!"

Black straightened up, a low, guttural laugh escaping his throat. It wasn't a laugh of amusement, but one of sheer, unadulterated contempt. He wiped the blood from his mouth, looking at the crimson stain on his glove as if it were a fascinating curiosity.

"You still believe it's about mere power?" Black's voice was a venomous whisper that carried over the battlefield. "You two, for all your strength, are still blind. You see the battle, but you are ignorant of the war. You fight for your precious lives, for your fleeting world. My purpose is so far beyond your mortal comprehension."

His Rosé aura flared, but it was clear he was on the back foot. The combined, coordinated assault of the two Saiyans had pushed him to his limit. A snarl of frustration twisted his perfect features. This was not part of the divine script.

"Justice..." he hissed, his eyes burning with a zealous fire. "The justice of a silent, pristine universe...requires more than just power. It requires absolute conviction. A will that is unshakeable, a heart that beats in perfect sync with one's own."

He raised a hand to the heavens, not to gather energy, but almost in a beckoning gesture. The very light around him seemed to dim, drawing towards his palm.

"To bring about the justice I desire..." Black declared, his voice rising to a fervent, preaching crescendo. "...I needed the perfect sympathizer as my ally!"

As the last word left his lips, a point of light erupted high above him in the polluted sky. It wasn't the violent flash of ki, but a serene, holy radiance that pierced through the gloom. The light expanded, descending like a gentle waterfall, so pure and intense that both Goku and Vegeta were forced to shield their eyes.

"What...what is that?!" Goku exclaimed, feeling a pressure entirely different from Black's malicious ki.

Vegeta gritted his teeth, his scowl deepening. "This feeling...it's not like his, but it's just as arrogant! Don't let your guard down, Kakarot!"

From the heart of the luminous descent, a figure emerged. The holy light coalesced, and you descended gracefully, touching down lightly upon the scorched earth between the combatants. The radiance did not fade but seemed to cling to you, a gentle corona that stood in stark contrast to the violent auras of the Saiyans and the sharp pink of Black's Rosé.

A beatific, possessive smile spread across Goku Black's face as he looked upon you. He was no longer a cornered warrior; he was a prophet whose messiah had arrived.

"The final piece of our divine design" Black whispered, his voice dripping with reverence and triumph. "Now, my fellow divinity, let us show these flawed creatures the true meaning of despair."