This is my 2d Shooter Project. These were my alterations. 

1. Created music for the main menu
2. Made a hand drawn cover for the game
3. Added a sprint function
4. made 3 levels with different levels of difficulty and made boss versions of some enemies. 
5. added new sprites for the player, two enemies, two different backgrounds for the levels, and everything on the main menu/level select/instructions.

As with my last two projects, i cant seem to build my projects for MacOs but i was able to get working builds for both windows and WebGl.