One-way traffic

Academy City.
A magical city with a population of 2.3 million, filled with countless people possessing extraordinary abilities.
Standing atop that peak is the true monster.
First, one side passes.
The pinnacle existence possessing the strongest and most malevolent power to truly control the direction of all energy; the strongest monster in Academy City, reigning supreme over all.
He will face encounters with countless worlds that transcend time and dimensions.
This is a world where countless whimsical ideas converge, a world of magic, a world of technology, and all sorts of people and things mingle together.
Then, the first person will experience all of this firsthand.
"—Interesting. Then let me see how your so-called justice actually works, my heroes?"
Having demoted himself to the villain, Accelerator, the most vicious and evil anti-hero, what kind of encounters will he have on this journey that transcends dimensions?
The strongest and most evil one-sided dark hero awakens here.
This is a crossover fanfiction featuring various anime and manga series, with Accelerator as the main character, aiming to recreate the feel of the original A Certain Magical Index.