Bones, older than entire races, begins to stir and move in ancient and primordial caverns, asembling themselfs into truly titanic forms of Dragons, the likes of wich the world hasent seen for epochs and will not see again. Bones that dwarf even the largest living dragon. This is the remains of the Ur-dragons, ancestors to their modern kin and true demigods in their age. Their wings blotted out the sun and their breath laid waste to entire continents. beings of extrodinary elemental power, their ancient souls, older than some gods still lingers and animates their sacred bones whean they seanse intruders. The ages have amde their bones harder than stone and their breath weapon is now a fossilizing miasma.
You should compile all this delicious lore into a book. This stuff sounds like the makings of a great epic. ^^