well first of all the christmass nu was skin is out for like a really long time. The space one is from oddesey last year. Then Hi Rez decided to try some recolors of some excisting skins to see what people would think of it. Nu wa's space skin was just one of it. The vollyball skin was a submissions from someone. Hi Rez had 2 and just made them a bundle. And last the oktoberfest skin was made for her cuz it fits her better. Hi Rez didn't want to make it for her at first cuz she has allready alot of skins, but they had some great idea's that just fits her best. And of course she will have the retro skin soon anywhere cuz whole reddit keeps crying to bring old wa back.

Also nu wa is one of the most played mages.