Disclaimer: I didn't finish the game. In fact, I couldn't be bothered playing it for more than 40 minutes (the game should be finished within 2 hours anyway).
There isn't really much to say here. As a 3D FMV horror-adventure game (played from a first person POV), this game commits all the sins its genre allows: slow, unskippable transitions whenever you walk, turn or pretty much do anything; story presentation is barely intelligible; cheap, pseudo "jump-scares" (if we want to call "slowly panning the camera to a corpse or a ghost hand from a mirror" scary); puzzles that barely require any intellect; a time limit; no save feature; devoid of interactivity; overuse of musical cues for its scary moments and so on.
But the biggest problems is that it's dull, which kills any attempts at building a mood. There is barely any context to the events at hand. In the intro, you are told your father suddenly went on a murderous rampage, and you try to go talk to him to understand what is going on, only to get sucked into a portal to a gothic castle. In the first few minutes, an apparition of your father explains to you that the castle is something akin to a realm in his mind, and that you should leave. You can also see weird, cryptic flashbacks when exploring, and that's all the story you get, until very close to the end, pretty much.
Having checked a playthrough, I'll only say the twist is so stupid, I'd accuse it of being written by an AI, if it had come out recently. Thanks to the fact that the characters are barely explored, it also feels totally undeserved (we know nothing of them so why should we care? More than a twist, this feels like the first introduction to one of the characters' traits).
The game is effectively the amount of gameplay and story you'd exepect for an intro, stretched over 2 hours, and it's clumsily delivered. All the praise I can give it is that it accomplishes what it sets out to do, even if it's an ill-conceived idea. Nostalgia is mandatory.