It is a z-axis Pike Visualizer for the Prusa Mini. Designed to show when the motor is spinning. Best printed with supports across the bottom.
Update1
Just uploaded a Swimming Pike version. Still experimental.
Update 2:
I have finished a new version of the swimming Pike. Now it is chasing a yellow perch. Works great and image showing it printed out. Needs full support to print properly. Fin on the perch is finick to print.
The author hasn't provided the model origin yet.