Pretty classic traditional shmup-- Good art and music! I don't know how much of the gamefeel is just provided by the engine but it feels nice and smooth, and in terms of level design the bullet patterns are quite beautiful while remaining fair. Really my biggest critique is just its adherence to the theme: It feels like a pretty generic shmup without much personality, and the only thing tying it to the theme of Unstable is just... Revenge bullets, a mechanic invented by the first ever "bullet hell" shmup back in the arcades with Dodonpachi. I think it could've been a bit more creative, but it's very solid!