This is my 2D shooter.

I have made the following modification.
I added 3 main levels
I added a new puzzle mode with 3 levels
I added an Endless mode
I added additional buttons in the menu to navigate between these options
I added portals, bouncers and bowerups(lives, shooting Rate), for this I made simple graphical elements, and reused images, and implemented the gaming logic in the different scripts.
I added custom music to the puzzle levels that I created with GarageBand.

I have tried to investigate as many aspects as possible, however I did not dive very deep in any of these aspects.

Credits:

Created By Sietske van der Honing

With use of Unity and Garageband

Images used: