Player A (Lvl 60)
Player B (lvl x toon)
Player A Opens the Game (black soulstone)
Player B Joins
Player A Kills Zoltun Kull
Player A+B Take the Soulston
Player A leaves the Game
Player B finish the Quest
---
Player A Resumes
Player B Joins
Player A Leaves
Player B Finish Quest
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Just Works on Normal and Hell not on nightmare.
repeat the red steps, u can finish the quest 10000000 times with just kill Zoltun Kull once.
its just an re-post because i didnt found this here.