Every component was tested and printed with PLA, 0.6 nozzle and 0.2 mm layer height. You can if course try higher layer height but in my case it doesn't keep good clearence and I have to make some grinding to fit.
Infill can be standard 20% except the holder that keep the ufo. It should be printed at 100% for maximum stifness.
Instructions.
After print you have to glue everything with superglue except the little man that should fit without glue.
In the UFO you have to put magnets. You don't need to glue them, just put them into hole and screw the cap, the more magnets the better. The hole has diameter 13 mm, so you can use magnet up to 12 mm diameter without trouble.
In the cow you have to make a small tail with a wire from a paper clip. This is enough to make some “levitation” effect. If you want you can attach to clip a magnet or glue magnet to the cow body. It should makes better effect of levitation.
You can use the base without the little man. There is a small hole to hook things you want, in my case I stuck some paperclips in there.
Upgrade
Version 1.1 - Added ufo with screwed closure. With this close, magnets stay inside ufo and you can play with it even standalone without base. (29.04.2023) - thanks @PendingPeril_217803for sugestion :)
Have fun
Have fun :)