Sulfur

Sulfur can be obtained from the Apiarian Phantom and other Hounds of the Wild Hunt. It is used to craft the following items:
 * Dancing star
 * Enhanced dancing star
 * Superior dancing star
 * Superior grapeshot
 * Enhanced moon dust
 * Superior moon dust
 * Greater red mutagen
 * Yellow armor dye
 * Zerrikanian powder

Sulfur is a yellow alchemical substance, well worth selling.