Seven hexes northwest, six north of Alakran.
Rising from the plain south of Eryptos, crouching with wings folded and tail coiled, regarding the back of Tiamat's great statue who in turn bends back two heads to look at it -- behold a statue, four hundred feet long and 120 feet tall, of the platinum dragon Bahamut. It is made, somehow, of crystal, but not transparent crystal. At night it is seen to be mostly opaque with a few eerie lights shining through translucent places.
Nobody has seen him in four or five years, but the inhabitant of this marvel is an ancient wizard called Kul-Gattur, titled The Mahal. Supreme of power in the eastern Wahatti lands is he, and the tutor of Eryptos' own master wizards Syrioth and Abru, but now he is assumed sunk in scholarly pursuits or planar sojourn. Thieves mutter about what riches he might possess. Indeed, the statue has four doors on the ground, one between the toes of each foot, but it is widely known that only one of these leads somewhere; the rest lead to death. Again, one might fly or climb up to the dragon's head, which has five entries, for mouth, nostrils and ears; but the odds are even worse, for all of them are ultimately lethal except for one.
What's inside is necessarily second- or third-hand news. Day's light, apparently, shines in through lenses and prisms with odd effects, sometimes blinding, sometimes creating chromatic magics, sometimes spilling illusions or hypnotic moires. Beings of animate light feature in the wilder tales. Then risk it by night! But dark whispers, too, circulate about what the lenses and prisms do to the shadows of the night sky and the scintillas of the moon and stars.
In conclusion, both the wizard's effigy and the great idol of Tiamat can be entered, there to face foes and haul, one hopes, great treasure. But when the dungeon is a dragon, anything can happen.