Doctor Galliard Prunestoggle is a literal giant, unofficially making him a Type VIII Construct. It is not explicitly revealed how he achieved this status, but the chances of it being Sparkily self-inflicted are pretty good.
He is among the atypically-disorganized swarm of Sparks/Sparky creations who get thrown at Mechanicsburg by Klaus during the Siege of that city. In his brief appearance in-comic, his initial arrogance and confidence (see image and caption to right) instantly vanish upon meeting Agatha and her large honor-guard of Jagermonsters. He insists that he has no information regarding Klaus's overall plans, and is promptly pummeled dead or unconscious. Agatha finds this whole encounter unsatisfying, and moves on to interrogating other members of the swarm. If he's still alive, Prunestoggle's ultimate fate is unknown.
See Also[]
Another giant who appears (much later) in the comic is Gritha Pantagruel. Apart from the two of them sharing a set of initials, there has been no indication they have any sort of connection.
Possibly relevant outside information[]
The source of the Doctor's name may be from the Galliard, a "gay" or lively dance dating to the Renaissance, 15th century or earlier continuing well into the 17th century, set to triple time. The dance is made up of complicated turns and steps in sequences of 5. This points to some interesting conclusions given his deployment to a crowded urban area.
Another possibility is the typeface Galliard, which may be more likely, given that both the Foglios and Cheyenne Wright have been working in the graphic arts for their entire careers.