"Articulated Crystal Dragon by Saber3D" had a few versions, namely the original and an "Updated" set of models that has better/thicker connecting rings.  The "Updated" models would not load in PrusaSlicer with the correct multi-material painting for some reason, and this fixes that.  It's set up for a 2T XL.

NOTE:  I didn't paint the model exactly the same.  Namely, you can see that the smooth "eyebrows", and similar horns on each vertebrae, are the same color as the base, but on Saber3D's version they are the same color as the crystals.  This could be fixed with some careful hand painting using "Smart Fill" and a good setting, but I haven't done it.  Just know they don't match.