Ghost Dragon

As dusk falls over the endless grass fields of the Jabari Plains a haunting sight traces across the sky, a flailing and growling form of a great gold dragon soar across the sky twisting and writhing in an unknown pain. It roars with a haunting hollowed voice like a creature screaming from an unknown void, it makes slow circles around a smoldering crater spewing ghostly flames from its mouth and yelling in draconic.
The crater in question is the smoldering ruin of the dragon's tomb, a massive burial chamber filled with treasure and built with catacomb walls and sealed with a massive heavy iron door at the far end. And at the other end is the chained and mummified body of the dragon, written across its bandage wrappings are draconic runes that glow with a sickly green arcane energy. The floor of the chamber is covered in deep claw marks and mangled and charred bodies, the walls are lined with dozens of grave nooks that house within them the skeletal remains of the dragons' former worshippers and disciples.
If the party fights the dragon inside its tomb, then it uses a roar as a lair action to summon 1d6-1 skeletons from the walls of the chamber. Additionally, the dragon gains the ability to cast spells as it begins to become enthralled by the arcane ruins placed upon is burial wrappings. The only way to enter the chamber is to jump or repel down from the opened ceiling of the tomb some 85 ft. above the chamber floor. If the party jumps, then the only back out is through the burial catacombs through the sealed iron door or through creative means of scaling the roof of the chamber.

Treasure

4,100 cp, 11,000 sp, 39,000 gp, 3,500 pp, 6 mundane items, 20 gems, 18 art objects, 5 magic items.
Mundane Items: Two stuffed chimeras, seven candle sticks each representing a primer god, a tarnished brazier of pleasant-smelling ash, a painting by an artist long forgotten to all but the dragon, a kneeling bench pointed toward a large marble platform.
(20)Gems: 1,000gp; Fire opal (3), Star Ruby (3), Star Sapphire (2), Yellow Sapphire (4), Emerald (2), Black Opal, Opal (4).
(18)Art Objects: 25gp; cloth of gold vestments, silver ewer (5), gold locket with a painted portrait inside (2), embroidered silk handkerchief, black velvet mask stitched with silver thread (4), Pair of engraved bone dice, small gold bracelet (2), copper chalice with silver filigree, carved bone statuette.
magic items: Potion of Storm Giant Strength, Chime of Opening, Potion of Greater Healing, Potion of Supreme Healing, Figurine of Wonderous Power (Marble Elephant).