Sethan

 Sethan is the stand of Alessi featured in Part III: Stardust Crusaders.

Appearance
Sethan takes the form of Alessi's shadow with a distinguished shape, the most prominent feature being its large eyes.

Ability
Age Reversal: Anyone standing in Alessi's shadow will age backwards at a rapid speed. Polnareff, who touched it for a split second, ended up as an approximately 7 or 8 year-old child, while a woman probably in her twenties stood in it for ten seconds and was reverted back into a helpless fetus.