Catchy graphics and environments, but the excitement doesn't last long. Poor gameplay, exploration and overall experience.
1. Passable combat system, nothing special; its lack of variability lead to repetetive fights, which are heavily based on reflexes. Almost unplayable on pc without a gamepad, due to the inexplicable constraint of the mouse.
2. Total lack of any kind of storyline/character development. The ephimeral hints are completely insufficient to make you care about the main character or any of the "events" of the game (nothing really happens). A common opinion is that this is a director choice. Even so, it feels like something done without much inspiration. Play Fez for instance, which similarly refuses to use any spoken word throughout the game, but with great results.
3. Uninteresting exploration. Extreme freedom of travel leads to an unbalanced gameplay experience. High difficulty gameplay done wrong. Even if you like hard games, this one only gets more and more frustrating. The environments are nice but not really exceptional, and the lack of storyline is a heavy burden for the exploration here. Again, to make a comparison, this didn't happen in Fez: even with almost no storyline, some hints and the overall atmosphere worked better. Finally, the score, composed by Disasterpiece, the same guy from Fez, is good but not really compelling as in Phil Fish's game: so "ambient" that it gets generic, even anonymous at times, and this doesn't help the overall atmosphere.
Feels like a lost opportunity for a great game.