Hydrargyros the Godburner is a deceased dragon; he is first mentioned in the post-continuity side-story "Franz Scortchmaw and the Story We Haven't Named Yet", as the plot of said story centers around an expedition by Franz and some others to loot his theoretically unclaimed hoard. When alive Hydragyros used a Sparky artifact called the Iram Solis to massively boost his weak internal flame, leading to the destruction and abandonment of a large swath of countryside around his lair; even Baron Wulfenbach's forces avoided the area. The potential claiming and securing of the Solis leads the Corbettite Monks to become involved in the expedition.
He is described as being a collector of books, which is what specifically leads to Franz getting involved.
According ✣ to Franz, Hydrargyos was once sent to attack Mechanicsburg, but Franz easily defeated him. Calling it a nice try, the Heterodyne of the time invited the attackers in for an after party and the two dragons discussed treasure, which kingdoms had the best princesses and other dragon stuff. Franz describes Hydrargyros as "cranky, touchy, a real grouch" and not a people-friendly guy.
The expedition is forcefully joined by Professor Blintzie von Wyrmhaut who seeks the Iram Solis, something that greatly worries expedition-members Vipsania Perrault and Brother Marcus and which the rest of the expedition, including even Blintzie's own students, don't know anything about. However, they discover ✣ that the door to Hydrargyros's lair can only be opened by Hydragyros' own unique dragon fire with all of Blintzie's attempts, including having Franz breathe fire at the keyhole ✣ , failing. The two attempts before Franz were fatal to the people who tried, but Vipsania reveals ✣ that she thinks that they can change Franz's flame to mimic Hydragyros' because she's very good at research, even with the dragon dead and thus not around anymore to supply an example of what they're mimicking. The attempt is successful, physically and mentally altering Franz just long enough that he can blast his way through the door; we also get, presumably, a further taste of Hydragyros's personality: the transformed Franz is greedy even by Dragon standards, selfish and even bit of a backstabbing whiner. Fortunately, the change is short-lived and Franz reverts back to normal.
After making it into Hydrargyros' lair, Blintzie reveals ✣ that her famed monster-hunter uncle Hengst was the one to kill Hydrargyros, but as far as she could tell, he was mortally wounded in the process, with her semi-dead minion Hector discovering his mummified corpse; before this, Blintzie's family spent years wondering what had happened to him. Further inside, the group also finds ✣ Hydragyros' skeleton lying on top of his hoard, which does indeed include numerous books.
During a battle with the Fun-Sized Mobile Agony and Death Dispenser guarding the horde, Franz locates the Iram Solis and uses it ✣ to destroy the clank. Franz reveals ✣ that, while Blintzie was thinking of it as a treasure, Franz had recognized the Iram Solis for what it really is, a tool, something that you'd want to grab fast on your way out of the door. As such, Hydragyros had hung it on his coat rack out in the hall.
However, the argument over the Iram Solis causes Hydragyros' ghost to rise ✣ above his corpse, angry about his glorious treasure being disturbed. After ✣ Blintzie is scared off, albeit with the Iram Solis, it's revealed that Hydragyros' ghost is actually just an illusion projected by Brother Marcus using one of the dragon's sparky defenses. As a result of the illusion, when Blintzie and Hector fled the lair, they fell ✣ into the bottomless pit outside.
Following the expedition, Hydragyros' horde is transferred ✣ to Franz's home in Mechanisburg.
Possibly Relevant Outside Information[]
Hydrargyros is the Latinized form of the Ancient Greek word hydrargyrum, meaning the element mercury or quicksilver (hydrargyros literally means water silver). This name is the reason the symbol for mercury in the periodic table is Hg.