Maybe in the future, there could be undead horses?
Wether or not they add it in the future is unknown. However, using the model that Funcum finished, but didn’t implement (but the source files were made available in the dev kit) I was able to create a mod for players to use.
Undead Horse Mount Mod (be sure to check out the Youtube video that is the first thing listed in the screenshot section for a laugh, if nothing else).
Very nice. I was expecting something like the Undead Dragon in the Arena.