Zola gets her gun - sorta.
During the eventful Castle Heterodyne plot-arc, Zola acquires ✣ a huge marshmallow gun in Lucrezia's secret lab. While mostly harmless, it is impressive looking, and she manages to kill Professor Diaz with it (wielded as a club) before Doctor Mittelmind uses his built-in pulse cannon to make it blow up in Zola's hand.
That Professor Mezzasalma already knows it was a marshmallow gun when some of Our Heroes reach him in the post-attack aftermath implies that Zola tried at first to shoot them with it. Zola not realizing that it was non-lethal (if used as a gun anyway) has cast some doubt on just how much reliable access she has to the memories of her "captive" copy of Lucrezia.
Print Novels[]
Agatha H. and the Siege of Mechanicsburg notes that (more or less) useless items of this sort tend to accumulate in Sparkish lairs, and nobody really knows why.
Speculation[]
The Marshmallow Gun may have been created as a lure for escaping prisoners, causing them to "arm" themselves with an imposing but useless weapon, rather than something dangerous. However, it can still be used as a club.
It must be said though that it makes a great edible, biodegradable improvement over the nerf guns of our universe. Perhaps it was created to make putting marshmallows into your hot chocolate not only tasty, but a real sporting challenge.