Waterdeep:Manshoon

Manshoon (man-SHOON) was the founder of the Zhentarim. He was killed 125 years ago, but survived thanks to the clone spell.

Unfortunately, instead of a single clone waking with Manshoon's mind and powers when he died, all of the clones woke at once, and all of them believed themselves to be the "true" Manshoon, while all the others were impostors who sought to usurp his power, and must therefore be eliminated. Thus began the Manshoon Wars, with Manshoon's clones vying to be the last Manshoon standing.