The scoring system needs some tweaks. Since score is based on kills and difficulty is based on levels, it can be easily abused by not leveling up. It also makes the pixel/magnet upgrades a detriment early on.
Yes, it's inspired by Braid. The creator admits as much. Even if it's not the most original concept, the ending makes it worth it. Oh, and one little clue: for the last level, don't think too hard. 5/5
 "Rebuild"){kind=icon}
 "Pixel Purge"){kind=icon}
 "The Company of Myself"){kind=icon}