Chapter 521

The Mystery of King Crimson, Part 4 (キング・クリムゾンの謎 その④), originally in the WSJ release, is the five hundred twenty-first chapter of the JoJo's Bizarre Adventure manga. It is also the eighty-second chapter of Vento Aureo.

Summary
Bucciarati opens a zipper on the ground, sending the small Coco Jumbo down a canalization. Slowly dragging himself and Trish up the stairs, Bucciarati reflects on the Boss' power, and tries to look for any weakness, the only being that the Boss can foresee a small amount of time in the future.

The Boss and King Crimson reappear at the top of the stairs, revealing that he has foreseen that move. Bucciarati then attacks from behind King Crimson with Sticky Fingers' arm which he put into the ground, declaring that he too has foreseen that the Boss would get out of the turtle in time and reappear.

Time is erased again, and the Boss sees Sticky Fingers' arm make a zipper on a column. Positioning himself for the kill, the Boss misses Bucciarati when the lieutenant grabs the slider's handle and shuts the zipper, propelling him and Trish up the column and they reaches the surface and meet Giorno.