Great gamed design and concept, I liked the idea of the different guns and how they were used, I also loved the metrovenia style where you have to unlock new abilities to be able to reach new places in the game.
However, I think you should add more sounds to the game to give the user more feedback on what is going on right now.
The dialogue boxes moves so quickly and I can't read what is going on.
I think the particle system should be enhanced or removed as it is currently just distracting and confusing the player.
But great job on the idea and the game consistency!