One of the things I like about Undead in D&D is the variety of circumstances that lead to the different undead. I like to use these as game story elements and a bit of world building/cosmology.
I thought it would be neat to create a list of the varieties from the sources I have for reference purposes.
I plan to update the second post with cumulative information as I go and add individual posts for various sources after that.
If you see I've missed something please point it out, thanks.
This is an intriguing idea, and one I haven't ever given much thought to...or, rather, only with certain types.
Let's see what I kind of always assume/think in my games, without ever really acknowledging or using the reasons (except, rarely, for the very powerful "unique" types of undead):
Skeletons: are basically just magically animated remains/corpses. They are, for the most part, "mindless" and possess no actual individual will, a limited capacity for reasoning, language skills (in all but the rarest circumstances), or any remnant of the original being's soul. Most commonly, the re-animation process is achieved through the use of necrotic/negative energies, be it spell work, ritual, magically "infused" area or terrain, or any other number of ways. Most often these energies harnessed/utilized through the spells of the "school" of necromancy, though conjurations (infusing the remains with a negative energy sentience or some generically malevolent spirit) or powerful transmutations can be similarly effective. A cleric's "Animate Object" spell might work on a pile of bones to form a skeleton just as well as any "Animate Dead."
Zombies: exactly as per skeletons but with the introduction (which we will see carried through) of the element of "Hungering" added. They are after something from the living. For some, and most commonly in the popular culture, this is merely "brains" of the living. For others it may be include their flesh or an unconscious propagation of their kind, as with the common "zombie-making/-spreading disease/apocalypse." Otherwise, they are as mindless and soulless as skeletons and produced -unless you are having/using the zombie-spread disease trope, which I do not. Such is for more powerful beings to come- in the same ways.
Ghouls: So, here, we have the undead that are just above "mindless", to a more 'bestial" kind of awareness and existence. The ghouls includes 1) "the Hunger" of their zombie-kin, but also
2) a wicked cunning and wild animal-like ferociousness we have yet to see from the mindless/reanimated undead
3) an extreme of uncivilized behavior that instills immediate horror/disgust
4) introduces the D&D trope of the undead TOUCH doing something nasty/dangerous
and most importantly, 5) the introduction of "sin" and/or extreme depravity into the [D&D] undead creation "formulae."
Of almost equal importance,
6) the possibility and D&D trope of the Undead creating more of their own/replicating themselves.
To my mind, ghouls have always been, in any edition, the first, real, "Oh$#!t!" undead encountered. Not just because they could kill you -easily- or because they had a paralytic touch, but because they could take your beloved character and -if they didn't just tear you to shreds and eat you- turn you into one of them!
I have seen/read that ghouls are the undead result of those that were cannibals in life and/or died as a consequence of severe gluttony. Part of the curse of their undeath [as each type of undead surely has] is they are never sated, ever-hungering for more. I can work with that. Though, for my games, the true way they multiply to the numbers of their "packs" that are often encountered or bring an entire town/region to its terrorized knees, is the spread of their corrupting disease...not dissimilar to vampirism...called, simply, in my world, "Ghoul Fever." Creatures that are injured but not slain by a ghoul's [bite or claws] touch, must make multiple saves over the next 24 hours or succumb to turning into a ghoul, with a ravenous craving for living flesh and blood. The application of a magical Cure Disease [or equivalent, such as a paladin's touch] or Remove Curse will prevent the transformation, but once 24 hours have been completed, the change is irreversible (barring a Wish or divine intervention or some such).
Shadows: Here we have the Hunger, the bestial/more-than-mindless/instinctual awareness, the Touch, and we introduce the concept of something that is not entirely "real" or tangible/corporeal. As a result of that, we also introduce the need for magical damage/weapons to defeat it. Though simple bright light or -in many incarnations- the day time/sunlight can [might?] keep it at bay. Depends on the edition, I think, but Shadows -coming form the "Plane of Shadow" (or later edition's "Shadowfell") were not always considered undead. Sometimes they are "umbral" or creatures of shadow-stuff. In some games, I have seen it bandied about that shadows are the result of corrupt bad/evil greed, their undeath cursing them to an existence of having nothing...only contributing to their blind hatred and malevolence toward those that DO still have possessions -a.k.a. the living. Some of that is fine, but I"d stop short before making that a sole raison d'etre for all shadows.
I, personally, like them as the low-level/introductory kind of incorporeal undead. They're still from the Shadow plane [whichever one you use], which in most D&D cosmologies, abuts the negative material plane, so you're getting that necrotic energy influence to generate shadows out of the plane's innate beings, or just "atmospheric stuff." So, for me, shadows are the result of souls of low level or not so terribly "evil," but still "bad" people whose spirits don't move on to the higher planes, but are stuck in the umbral afterlife "mire" of this lower-leaning realm....and they are, understandably, pissed about it. Their anger and hatred and despair for things of light and life [beings that are alive] is a blind, almost mindless, hatred for these things and "snuffing out" the light of life anywhere they can is the only "warmth" they receive in their state of perpetual darkness-shrouded chill (a.k.a. their Strength draining touch). True to, I believe, most versions of the creatures, they are multiplied most simply by those slain by a shadow, rising up/becoming a shadow themselves unless a) a Remove Curse is cast upon the body "immediately" (let's say, within 24 hours) or b) the slaying shadow, the new shadow's creator, is destroyed -releasing their spirit/soul to carry on to its rightful place (and hence, the possibility of returning the slain being to life via the usual channels).
Which brings us up to...
Wights! Herein, we have the Hunger, the Touch (the original "real" danger of undead touch: Level draining!!!], the need for "magic" to properly damage/destroy them, the ability to Replicate themselves, and we introduce the WILLED undead! Those capable of -though not always allowed to act upon- their own thoughts and purposes and goals. Often brought about as under a curse. Often associated with greed, possession of -or obsession with- riches and/or earthly power. I have, sometimes, read/heard of them being cursed murderers as well, but this seems, usually to be murder with the intended goal/outcome of achieving riches or worldly power that curses them. We finally have the introduction of an undead who can THINK and reason, who possesses/remembers at least some language, skills, knowledge, ability at arms -now with preternatural strength and speed. This is something...truly dangerous. A villain all their own, not just driven by base desires. And something capable of, literally,
killing you with a touch, only to rise -within minutes- as another wight under its thrall. A wight, properly role played by a DM is a terrifying thing to behold. While possessed of a malevolent will of their own, and normally found alone or in small numbers in far removed locales, their capacity for thought and reason and speech makes them a favored underling for the more powerful free-thinking under or powerful wizard/necromancer.
I'll stop here, because now we'll shift into the beginnings of the truly powerful -and horrifying- undead.
