2dShooter

This is my 2dShooter project. I did these actual modifications:

- Added levels of different difficulty (I have 8 enemies for level three and 12 enemies for level four).

- add some obstacles (asteroids) to the third and fourth levels  (Level four has more).

- In the fourth level, a shooter was added to defeat enemies together, and when one is defeated, the other can still work (I created a C# script to set them to always next to each other).

Credits: Created by Chenglin Fan