Mystery No Arukikata 01008a401feb6000v0jp Top -

So, the user could be referring to a game, a book, or a website related to mysteries. Given the structure of the query and the mention of a "long guide," it's possible they're asking about a specific game, perhaps a visual novel or an adventure game, given the "arukikata" (walking) part, which in Japanese games can mean a visual novel walking simulation.