Pangu`s Axe once belonged to Dong Huo, Scourge of the Three Lands. It is a very exclusive item that can smash large boulders and clear rubble piles instantly. It can be found in the Temple of the Axe tomb in Shang Simla through an adventure.
Pangu's Axe can very easily be obtained through cheating. First, one needs to type "testingcheatsenabled true" in the cheatbox, and then type in "buydebug". This makes available the buydebug buy-mode category. In this menu Pangu's Axe can be bought and placed on a wall, just like a normal decorative object.