Well, it's the game I'm always browsing marketplaces to find, but never seem to, haha. Behind the Kingdom is meant to bring to life (via gameplay) the kinds of fantasy media experiences that were common in the 80's when I grew up: vast kingdoms, unapologetically epic adventure, light & unforced humor, some quirkiness, some wholesomeness, not overly gritty or existential. Mechanically, parkour-flavored games have always been my thing, especially the "Ori" series, so I planned from the beginning to have a metroidvania-style game with tons of movement upgrades that take you across the map, but also "up and down" the map in areas you thought you'd already fully explored. Also, I really wanted a basically seamless world with no loading screens to really give the feeling that the places in the world truly all inter-relate, as opposed to a bunch of separate zones that happen to be linked together. I want a game you can really disappear into like a book. (but a mostly action book, haha)
I don't want to reveal too much about the story yet, but I'd say the central trope is a gifted warrior who was chosen as a pawn for powerful beings begins to suspect he can subvert their will, and learns how while also learning to heal some of the pains of his world.