I copied the design of the original, only taking the ridged back. I created the mouth, side holes, and the resonance chamber with boolean objects in blender. The Politoed model is ripped from Pokemon X, and rigged and animated to this pose.
A dowel or pencil, placed through the hole drilled through the Politoed cheeks, is used to make sounds. An object is then dragged along the ridged back to make a "ribbit" noise.
CC3D PLA 1.75 mm
Green or Yellow-Green
ABS 1.75 mm could also work.
How to play the instrument
A pencil or wooden dowel can be used in place of the bat to make a "ribbit" or "rivet" sound. The frequency depends on the size of the frog; smaller frogs produce higher notes. A PLA frog at 80% scale has a nice resonate tone. The best sounds are made when the rod is dragged from the rear of the frog towards the head. Copied from the original thingiverse model
I have yet to test this instrument, will edit once I am able