Sethan
Sethan (セト神, Seto-shin, lit. "God Set") is the Stand of Alessi, featured in the third part of the JoJo's Bizarre Adventure series, Stardust Crusaders. It is also a member of the Egypt 9 Glory Gods, a group of Stands representing ancient Egyptian gods.
The Stand manifests itself within Alessi's shadow and takes on the appearance of a humanoid with a round-like head, or when it faces sideways, a bird-like head. Anyone who touches it will be de-aged in body, mind, and soul.

Image attribution details
Sethan. Source illustration via JoJoWiki; copyright remains with the original rights holders.
Image via JoJoWiki. Original franchise/production rights holders retain copyright; the wiki text CC BY-SA license does not license this image.
Original image ↗ · Archived image ↗01Basic information
02Appearance
Sethan is bound to Alessi's shadow, taking its form but with a distinguished shape, the most prominent feature being its round head, a pointed crest, and large eyes. If the shadow is sideways, Sethan's cruel, jagged beak is revealed.↗↗
Its design is based on the opening of the Tetsujin 28-go anime, as well as the Nazca geoglyphs.↗↗
03Abilities
Sethan is a weak Stand with almost no offensive options, relying on its esoteric power to make its opponent weaker than Alessi. However, this alone makes it a terrifying opponent to face.↗
Shadow Reflection
Because Sethan takes on the form of Alessi's shadow, it imitates and replicates everything he does and has.↗↗
Because of this, any weapon Alessi holds is also held by Sethan, allowing it to attack the opponent with the shadow of the weapon. Moreover, the shadow can move independently from its possessor and even partially stick out of a surface to attack.↗↗↗
Age Reversal
Anyone standing in Alessi's shadow will age backward at a rapid speed. If a Stand user is de-aged to before they acquired their Stand like Jotaro, they will temporarily lose it.↗↗↗↗
The mind of the target also ages backward, leading their memories to progressively degrade into vague recollections of things they only knew as an adult (like names of friends or how to manifest a Stand).↗↗
If the user is knocked out, all the victims it affected will revert back to their original state.↗↗
04Plot details
SPOILERS
05Appearances
06Sources & attribution
- Sethan
