Kamen Rider: High Beam Rider - Starting with Saber.

Lan Su, who unexpectedly gained the power of light and darkness, was hunted down by the Black God.
By chance, he arrived in the world of Zi-O and obtained the "Oma Zi-O Chronicle," a combination of fantasy power and Oma Zi-O power!
The Black God is asleep and has not fully awakened.
This gave Lan Su a chance to catch his breath, and he embarked on the path to becoming stronger.
Power of light and darkness + omnipotent fantasy + power of omnipotence + power of creation! Is this a promising idea?
After obtaining these powers, he arrived in the world of Agito and declared, "Black God, you are the true challenger!"
As he traveled through various worlds, he also made up for the regrets of many knights!
Are the Four Horsemen of the Reiwa era too abstract? Was Oz's crafting a decade-long project? The helpless forgetting of Zero and his sister? The tragic endings of Marco and Yuuka in 555?
No! I'll decide how the story ends!
(No OOC, the knights also have their own highlights, no system, and there is a female lead.)