Most likely a work in progress, so I won't comment the lack of UI, I'll just make two observation : 1. even in dev state, why do you use the 100% green color ? It's so unpleasant. Please cap the saturation of the colors you use. 2. the only raise of dificulty for now is speed. It makes me think of the berzerk games, they were fun in the early game, and turned to be just luck based when the speed turned too high. You NEED to find other tools for the difficulty curve than just the speed.