Really like this!
Good graphics, nice little flourishes (loved the teacher getting grabbed by the tentacles) - really fun game play and a great sound track.
The blocking off and opening of the map via the weapons, and destroying the "generators", worked really well.
The final boss, was lots of fun, it took a few attempts to kill it saving the teacher.
The invincibility frames and push back could possibly do with some tweaking as a couple of times I got pushed back only to die, especially when facing the final boss, also new game doesn't seem to clear out everything (ie you can start with your weapons etc). But these are minor points... great entry!