For only having worked on it one day, this is quite impressive. The time scale slow on kill effect was a really good touch. And having multiple stages was cool. Wasn't expecting that on the first playthrough.
I would like to be able to attack while moving. Maybe in round two that could be implemented (if you continue this entry).
Music on the ending screen was both fitting and made me want to play again. Really cool choice there.
Good job overall!