Manga by author Aizawa Daisuke - Status ongoing

Just like how everyone adored heroes in their childhood, a certain young man adored those powers hidden in shadows. After hiding his strength and living the mediocre life of a mob character by day while undergoing frenzied training by night, he finally reincarnates into a different world and gains ultimate power. The young man who is only playing at being a power in the shadows, his misunderstanding subordinates, and a giant organization in the shadows that gets trampled.. This is the story of a young boy who had adored powers in shadows possibly eventually reigning over the world of shadows in another world.

Based on the Gatcha auto battler video game. Focuses on recounting the past of other characters and intermediate stories that occur during the main story which are also canonical.Not the main character, and not the last boss. The one who lurks in the shadows of the storyline and holds all the power, hiding his true abilities by acting like a side character. The boy who longs to be a 'Shadowbroker' lives an unobtrusive life as a side character, training to gain magic power until he's killed in an accident and reincarnated into another world.Reborn as Cid Kagenou, the boy decides to enjoy himself in this other world with a made-up scenario about "the Eminence in Shadow." He starts fooling around with secret maneuvers against an evil cult that he born from his imagination... and it turns out that the cult really does exist! The girls he took on as his subordinates on a whim began worshiping Cid as Shadow, and before he knows it, Cid has become a true "Eminence in Shadow." Before long, Cidalong with his mysterious group the Shadow Gardenwill destroy the darkness of his new world.The Strongest MC x Overwhelming Chuunibyou x A Serious Comedy Full of Misunderstandings!