DISCLAIMER: Your Steps and Tasks may be different
Ildanar, Underground Forest (loc 12438 11227)
1. Talk to Ildanar and get the jar. Travel to The Otherworld and find a Shar. I killed a Maniacal Fighter just south from the entrance at loc 21200 16800.
2. Return to Ildanar and hand him the jar
Level 42 Cleric got 465,000,000 xp and 1 gold as reward