How does King Crimson work?

The series Jojo's Bizarre Adventure by Hirohiko Araki contains many complex abilities throughout the many parts of the series. But not many can compare to the ability King Crimson. Many fans of the series have had issues contemplating the abilities of the complex stand, mostly due to being generally confusing, and inconsistently displayed. Firstly however, we should get a few things figured out before diving in.

What is Jojo's Bizarre Adventure?

Jojo's Bizarre Adventure is a manga series written by author Hirohiko Araki. The story follows the lives of the Joestar bloodline, with each new part showcasing a different Joestar member. The main power sets of the characters ever since the third part "Stardust Crusaders" have been Stands. Stands are physical manifestation of one's fighting spirit which are (mostly) unable to be seen or interacted with by people who aren't Stand users. Stands are often obtained through being stabbed by a mystical arrow head, however some can come through family or just with birth. Stands are generally used for combat, and have diverse abilities though most have limited ranges.

What is King Crimson?

King Crimson is the stand of Diavolo, the main antagonist of the fifth part "Golden Wind". In the series, Diavolo is the leader of Passione, one of the most powerful mafia forces in Italy. Diavolo attempts to bury his past and keep his true identity hidden from everyone, even his most trusted subordinates. He also has Multiple Personality Disorder, and despite being the dominant soul, puts the most trust and faith in his alternate personality Vinegar Doppio, even if Doppio does not know Diavolo is a part of him. The selling of drugs across Naples leads to the protagonist, Giorno Giovanna, joining Passione in an attempt to overthrow the boss.