Editing Periodic Table of Dragons (section)

==Thorium 90==
Thorium dragons are massive, heavy creatures, with the dull silvery appearance common to most members of the Metallic dragon subspecies. 

As with many of the heavier varieties, they are surrounded by an invisible, heatless force, capable of poisoning and killing those mortals who dare to come too close. 

With such protection, almost all the Radiant Metallics are peaceful creatures, having never had a need to defend themselves, owing to their size and energy. The Thoriums are particularly congenial and friendly, though still no less deadly. 

Their breath is a strange, invisible gas, which carries the heatless death property of their bodies. It is much heavier than air, and though its range is limited, it pools, eddies, and is extremely hard to remove. Historical records indicate that a wealthy Drow noble made the terrible mistake of capturing a young Thorium dragon for his coliseum, and when the furious parents showed up to rescue their child, within a hour the underground cavern was devoid of life. 

Even now, the city remains, filled with invisible death and lacking breathable air, a perfectly preserved monument to the folly of chaining forces beyond one's control.