I feel unqualified to review this game, so I won't contribute a star rating. A lot of it seems great in concept, like the combo and level up system, but they feel like elements that only can really shine if you dedicate yourself to learning, solving, and memorizing the ideal patterns of enemies to kill. Otherwise, it seems like your weapons would be severely underpowered for the rest of the game. With the story mode and save file features, it transparently feels like the player can elect to replace that skill barrier with raw persistence. Even with that handicap, I could only eke out a victory on all six stages after maxing out all my weapons AND bumping the difficulty down to easy.
The story. Uh. Between the compounding obfuscation of cultural differences, nonlinear storytelling, sci-fi philosophy, and a terrible translation, I don't think there's enough left comprehensible enough for me to give an opinion on. Remarkably bleak for both the gameplay and aesthetic genre used.

Currently very broken on PC, between the pause button crashing the game to utterly terrible framerates and regular slowdown. I feel like it wasn't that bad when I started playing the game, but that was like a year ago, which itself speaks to how the game itself didn't really grab me. The level design feels sprawling, but never particularly rewarding or engaging to explore, as you're usually rewarded with only a few mediocre health pickups, or a power-up that you probably already have a copy of from earlier in the level.