bla6546: Ooh, yeah, your solution is even better. Fits RazorMonkey's advice of only checking the collisions of those sprites in particular. You shouldn't even need a subevent; but you might want System -> Trigger Once While True
I've been testing this on a demo I threw together for another problem someone was having, but check it out:
When the first two Enemies first are overlapping, they flash for a second.
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