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.
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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
Frozen this work only about ligthing and black screen