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Hidden Back Wall

Defeat 60 Roaring Warriors then pass through Undead Cavern to the Back Wall. Defeat the Ghostlord Stinger there then return to Spy Ghost.
 

Show Quest Info

Introduction

Behind Taithon is a hidden passage called the Undead Cavern that leads to the Back Wall where Chiyu's general, Ghostlord Stinger, awaits. Pangaea Catacomb was built by the Yellow Emperor himself and is imbued with his will. Having sensed Chiyu's release, it sealed off all the major passages. To find Chiyu, you must first defeat Ghostlord Stinger and reopen the passages.

NPC Dialog

The path to Chiyu's chamber is not long, but is saturated with traps. Destroy the monsters here, then proceed to the Back Wall through the Undead Cavern. Chiyu's general, Ghostlord Stinger, is there. Defeat him to de-activate the tomb's security mechanisms.

Quest Completion

All the tomb's security mechanisms deactivated at the same time. Taithon must have helped you out.