If you read the story you will get a feel for the decorating and funeral preparation rites that required decoration of the corpse. I didn't get specifically into the reanimation of the body to walk with the rider.
This is one of those archetype character roll that sort of give color to my roleplaying game. I want to create something like a prestige class around it but I am not sure what to do her.
I am a big fan of the Harp game rules and have thought of just doing it as an encheapened skill set like they do in that game, but something doesn't feel exactly right there. I have thought yes it should give a block of skills or a cost savings on skills but something else too. Maybe there could be combat maneuvers or spells that are granted access too or perhaps rather than just allowing for cheaper purchase of skills I cold give out a fully exploded copy of a few skill trees. Maybe even not conforming to the normal rules so certain abilities are granted that may not normally be given.
With that i could restrain the magic while still giving some high end necromantic abilities. I don't want these guys being necromancers or shadowlords but I do want them able to raise a walking pile of bones.
Image taken from http://www.blackgate.com/2010/07/21/on-writing-fantasy-a-timeless-style/