Hey man, loved the idea of the game, however it seems to be a little buggy on my end. As soon as the enemies start appearing, the player sprite gets moved up into the air, but the collision and bullet shooting still takes place on the ground.
The mechanics are pretty good too, much I feel a little frustrated when I encounter the green object. It deals an instant kill regardless of what my health is, and is not clear what it is when you first play the game. I would recommend that you make some sort of a tutorial for the game, as it will be easier to understand what is going on.
Lastly, the level starts getting crowded very quick, so I would suggest that you make the level a little bigger and give the player some sort of terrain benefits.
Eager to see what you have planned for this game!
Thanks for the reporting the problems. I also feel the enemies are spawned too fast that the player may have no time to prepare. Probably because i have played it so much time so i felt it normal. I will fix this later. About the bug you mentioned, i don't really get it. Can you explain more about that?. And i will add the tutorial.
And maybe you should know this. This game is my entry so it's a once-developed game (i hope you understand what i'm trying to say), so i will improve all of the missing feature in my next game.