Streamer and world-first WoW raider imexile and his group have found a new way to farm Forgotten Souls quickly! s are a rare material to reroll Sacred and Ancestral items in Diablo 4. It can only be found in Helltides by opening chests, killing rare monsters, and opening Scream Hell Veins, a particular ore node that only spawns in Helltides.
As it appears, groups can coordinate to open Scream Hell Vein nodes one by one and collect more s and other materials that way.