Franz Scortchmaw is a large sentient scaled winged fellow (yeah, a dragon, though he's more bipedal than most) who has officially served as a Heterodyne monster in Mechanicsburg for a couple hundred years or so. He's not sure of the exact dates, because he spends a large portion of his time sleeping in an underground cavern in the general vicinity of Mamma Gkika's. (Which is where we first meet him.) He has been enhanced and adorned with various bits of Sparky tech, including gauges that show his current power-levels. Befitting his name, Franz can also .
Franz and the Siege
When the Doom Bell rings announcing Agatha's official ascension as the new Heterodyne, he awakes and comes forth to do his duty, lugging a very large sack full of gold. (Who better to guard a treasure hoard?) His first official act is to a clawful of the sack's contents onto the prostrate soldier of fortune Baron Oublenmach, as a reward for the latter's dragging the Doom Bell's striker all the way across town from Mama Gkika's, where it had also been stored. He then uses the bag as a bludgeon against the various monsters and constructs attacking Mechanicsburg. ( ) During this, he is to Agatha, and makes the ceremonial offer of having her roll around in the Heterodyne treasure. He's not particularly put off by her refusal; when he's not actively fighting, he comes across as pretty casual and laid-back.
And then comes his confrontation at the gates of the city with the aforementioned Pretty Boy, a more traditional-looking dragon in the employ of Baron Wulfenbach. The battle doesn't go well at first, since Franz's power reserves are so low, but Agatha with a blast from the Zappy Stick, which peps him right up. (His gauges and eyes actively glow when fully charged.) The fight is interrupted by the arrival of the Real Knights of Jove, but evidently gets picked up later off-screen, as the next time we see Franz he is wearing part of Pretty Boy's gear as a hat.
Despite having wings, he is unable to actively fly the way birds do, most likely due to his strength to weight ratio. However, he can Master Barry that resembles a bicycle carried aloft by ducted propellers that are driven by a long chain. (It's implied that previously, he had attempted to use birds and kites..) He uses this device to transport Agatha up to the roof of Castle Heterodyne, where she plans to re-charge the Castle the same way she helped Franz. They are interrupted by the Klaus-controlled Gil, who jabs Franz with a large sedative needle, putting him out of action. But only temporarily; Franz fairly quickly recovers and at Agatha's enraged direction, kicks Gil non-lethally out of the city while Agatha gets on with the re-charging.by using a contraption which was made for him by
Franz is presumably trapped in Mechanicsburg when Klaus drops into the city and activates his Take-Five Bomb.
Possibly Relevant Information
Agatha and Franz's flight to the Castle is depicted on the cover of the fourth Girl Genius print-novel, Agatha H. and the Siege of Mechanicsburg.