Clans are a useless game function. They don't do a thing except watse Greenhearts.
Gangs are characters from fandoms you like and OCs.
WoF doesn't have gangs but flipsides if you join GvE.
Flipsides are OCs often related your GvE-sona. Flipsides are bound together by the flipside bond. If someone kills a flipside, all others die.
GvE is Good vs. Evil, but there aren't actually any good or bad sides. There's the light side and the dark side, plus the Fusions, Chaos and Mercs.