In year 2300, The Gates suddenly appeared on earth. This event later was know the beginning of Era of Magic and Cultivation.
The Gates were quickly and swiftly conquered by Advanced tool of humans after which they were introduced to dark energy also known mana, spiritual qi, etc.
Humanity through countless simulations and research developed the way to use these energies and a few lucky ones awakened innate talent. The talent to be on top of that category.
Then shortly after year 2321, a tower seemly having no end appeared out of no where and connected them to centre of Multiverse.
They soon out of fear of unknown launched their most powerful missile that the had now enhanced with mana. But the result was that tower stood unscathed. Not even a scratch was seen.
Out of Curiosity, some powerfull awakened entered the tower swiftly climbing and reaching the safe zone, the 10th floor where resided the enigmatic races of different realms and universes.
They offered a helping hand to human by offering them map and techniques in exchange for their knowledge of pure science as those with something total focus on something was rare even in tower.