I can’t seem to find the specific rules for animating (via animate dead) or creating (via the create undead line of spells) undead war machines.
I suspect that it is as simple as casting animate dead,but is the resultant creature a skeleton or a zombie?
Also, some of these creatures have a considerable amount of hit dice. Under 3.5e rules, skeletons over 20 HD cannot be animated, and the limit for zombies is 10 HD (these HD are doubled by the zombie template, however). Are these limits dropped for undead war machines, like they were for the undead dragons in 3.5e?
I’d imagine that undead war machines would be constucts or magical vehicles and that necromantic spells would just be a part of their creation process.
I’d check out the Arms & Equipment Guide or the Stronghold Builders Guide for relevant rules.
Prestige Class Appendix 2, in the Royal Animator entry, designates them as undead under a control pool (most likely animate dead). That’s the sum total of guidance we have in the published material.
BTW, if the Royal Animator ever gets updated, I’d like to do the work on that. Basically it’s broken in almost every ability, and should be revised.
Undead War Engines, otherwise known as Vecna’s War Engines are unholy amalgamations of hundreds of undead fused by uncanny sorcery possibly powered by the Realm of Ravenloft, by epic spellcraft, or by divine power. The characters run into the wreck of one, and suffer if they are stupid enough to investigate it.
They were introduced in the Vecna Reborn adventure, middle issue of the trilogy. To my knowledge, no stats exist for them, let alone their creation method. Given that Vecna was considered a demigod around that point, it is highly likely to be an Epic Level Spell effect at a minimum, possibly the result of a Salient Divine Ability instead.
The only official mention of them in 3rd edition is the (former) Official Fan Site: Kargatane’s Book of Secrets, which is merely a lore reference and a picture.
As it was created by a demigod, you are probably better off crafting a golem or animated object with undead grafts or something similar. Maybe a locomotive train of them so that the individual cars can link together into a large war machine?
If there are any Dark Sun references to them, I have not yet run across it myself.
War engines, and undead war engines, are canon in Athas since the 1990s. If anything, later products like the one you mention took inspiration from Dark Sun.
I imagine that it is no surprise that I was unaware of them, what with my extreme dislike of magic in general and in particular in Dark Sun which already has far far too much magic.
Lol. The only thing I’ve ever looked for in the Dark Sun rule books is psionics, so I’ve probably never read that stuff before.
If there are not clear rules for creating giant undead war machines, then I suggest using the Lifeshaping rules as a base (since they at least allow for the creation of creatures at the top end of the size charts), and tweak them a bit to work for undead.
Maybe add the Titanic template from Savage Species, again tweaked as needed for undead.
I have no idea what the original Athas dot org team had in mind, but I suspect it was just animate dead of a specially prepared giant animal or giant vermin. And like dragons, their HD is not limited to 20 HD when becoming a skeleton or zombie, and the HD of the war machine zombies are not doubled. That’s the most straightforward way of dealing with it. It’s also the most consistent with Dragon Kings.
I saw Furiosa a few weeks ago and it really got me thinking about war machines.
Maybe after Unseen Ways, I can tackle Lifeshaping. I have heard a number of complaints about the rules as currently constituted, and the concepts are within my areas of interest.
If you wanted to create an undead war engine, technically it can be done with a regular create undead. I do not know where you got the limitation on HD though! The Animate Dead spell does not come with that caveat. The trick afterwards comes in with the retrofitting.
I couldn’t find that stipulation about the HD issues, so I have a couple of options without going into that. So using the size options roughly as follows:
Large - Could do a Chariot. Could be inside if cramped or small sized
Huge - Could Possibly be inside the creature. Mounted conflict. Truck/Sedan
Gargantuan - Battle Bus!
Now with the limitations on the 20HD situation, you could do a Gargantuan vermin like a Monstrous Centipede or Monstrous Scorpion (exactly 20HD). I would recommend going with Skeleton for those. Since its all exoskeleton, you could then use the inside an retrofit arrow slits and have a perch on top. For smaller situations and aerial units, one could use Zombies for things like Giant Wasps. They would keep their fly speed with poor maneuverability, and turn into 10d12 undead so harder to shoot down.
A more setting specific undead could be the Watroach from Terrors of Athas. Gargantuan, 15HD. Notably large enough that it has the Swallow Whole ability.