This is a bobble-head Gnome toy.  This toy uses a 3D printed spring and base.

Supports are required only for the Gnome body and you can use minimal infill for all parts (10% is fine).  

This was made from a couple of different things.  First is the excellent Gnome model by BODY3D (https://www.printables.com/model/178691-gnome-christmas-tree).

The spring mechanism is based on the excellent bobble head collection designed by 3d-printy (https://www.printables.com/model/224836-emoji-printer-bobbleheads).  Be sure to see their extensive collection of bobble-heads and other items.

Bobble-Head Assembly Tips:
The square spring hole in the gnome is a little oversized to aid assembly. Install the spring into the gnome first (crazy glue is recommended).  The tool to install the spring is included here and its use is optional, but recommended. Install the magnet (8 x 3mm) into the base (optional) and finally the gnome/spring assembly onto the base (glue is optional here).

Enjoy!