Tribal in nature, a nigger flash is an action where a group of uneducated nigger thugs "youths" attack and rob innocent bystanders in public places, ie. bus stops, metro trains. Nigger flashes tend to be violent and senseless, but can be correctly explained as "that's what niggers do", or "what do you expect from a bunch of niggers
". Said nigger flashes are directly proportional to the heat index and lack of lawful employment. Nigger flashes can be mitigated by "flashing" a .45 caliber or by throwing a bottle of Strawberry Faygo soda into the middle of the Nigger Flash.
Do not confuse a Nigger Flash with a Mob Flash
, which is typically performed by a bunch of lame-ass white hipsters with nothing better to do then spending their parents money while in college.
Yo, I just came from a nigger flash on the green line off Rancine Ave. I gots me a new Ipod offa some dumbass whitey. I hope it still under warranty.