Hi im intersting how make this system Shot em up i know i can make black screen and light but this no this same i show u video about Game Jam and see interesting game but dont know how make this 9:22 min youtube.com/watch sry for my eng.
Take a look at blend modes.
Have a look at the simple lighting demo in the beginner examples it will show you all you need to know to get this effect
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Frozen this work only about ligthing and black screen