An excellent idea that was pretty well executed. A lot of easy mistakes could have broken this, but pretty much all the major pratfalls got avoided with solid execution. I particularly liked how all of the different enemy types (of which there was a surprising variety) were clearly telegraphed in a way that made their mode of attack almost instantly clear on first sight. The only thing that stuck out to me as a clear place to improve would be the damage feedback: I didn't know I'd taken damage at all until my health was almost half gone! Otherwise, stellar, especially for two days. Take my five stars. 

It's really good, best game i have seen so far. needs chechpoints tho.