Cold Zombie and Undead Mount Variant

With the Mounts of Mayhem update we have gotten a new skeleton and undead Mount for the desert. However the cold bies still only have the Stray. I feel for consistency sake there should be a new cold zombie variant, which can apply the frost effect similar to powdered snow rather than an actual potion effect, as well as a mount for it to ride with a spear. My idea would be to make a zombie polar bear, which unlike a a normal polar bear is completely hostile and also cannot be ridden by a player. Another idea is the stray horse which is similar to the skeleton horse but can stand on top of powdered snow. I feel some sort of mount and a frozen zombie would be nice to make things more consistent though.