Commission by  inklop!

Emmet has a hobby of inventing all sorts of weird guns, each with its own unique effect. And to that end he maintains a "firing range" (underground, naturally) that he often retreats to in order to blow off steam—or lasers, or plasma bolts, or exotic boson streams.

(Sully's not allowed in there, for reasons that don't merit expounding upon.)

One thing's for certain: if the planet is ever invaded by a race of aliens with a very specific weakness, Emmet will be there, ready to patent and sell a weapon design to the military. At a very reasonable price, of course.