The video doesn't just go into the lore side of things but also looks at the physiology of the creature with some ideas and thoughts of how to approach them as player character, can they climb, where are their internal organs, additional fall damage due to their weight, are they bothered about...
Hi. How does the zombie cast the spells without the required components on its person? If your spirit is in the zombie surely you should no longer be in control of your own body to be able to cast spells through it? I'm also not sure how inhabiting the corpse with your spirit alone would...