Meikyuu Teikoku no Tsukurikata: Zensei no Kioku ni Mezameta Bannou Rensei Jutsushi, Anzen na Dungeon-nai de Muratsukuri Hajimemashita. ...... Are, Nanka Hito Fuetenai?

One day, Nino - an all-purpose sorcerer - regains the memories of his past life, and he realizes that he is in the world of a video game he was obsessed with in his previous life... and that based on the situation, he's right on route to reach the game's bad ending! So he takes the actions necessary to avoid the worst possible outcome, but this casts suspicion on him and leads to him being demoted and moved to a remote area on the basis of a wrongful accusation... But he soon finds that the village there is full of hidden dungeons that only he, through the obsession he had in his former life, knows about?! Source: MAG Garden