Hermeic Prosthetics

As promised.

I can see three means of making a hermetic prosthetic. Each with different costs, advantages, and disadvantages. The first is a mentum spell with rego and form requisites. This is one of the 2 all in one packages I can see working. Now I considered "reading surface thoughts" (15) but you aren't really thinking "move my hand, move this digit, etc." hand moment is more of an impulse, a state of thought, you can do it completely autonomous of your thoughts. So base 4.


(The prosthetic limb) Cooler name pending
InMe (ReTe) 24
T: Ind D:Conc R: Touch

Identifies the desired movement of the limb and moves it accordingly by moving the prosthetic accordingly.

Base 4 (+1 conc, +1 Touch, +1 Requisites, +4 constant, +5 maintains concentration)

I choose concentration as the device has to constantly change form with impulse. The fun of this one is you could have your hand running around a room like cousin It. The downside is you need to add another spell to let you feel anything. I guess you could add an additional Imaginum req to add that on.

This may seem a bit low, but I choose this method because your mileage will very with different forms if you make the base effect the Re(form). I have considered adding a +1 to do to complexity, and a +2 for a hand, given that it is far more precise. But first lets look at a Terem hand in the other all in one package and why I don't believe it works.

The Metal Leg
ReTe (InMe) 29
T: ind D: Conc R: Per

Causes a metal limb to move in accordance with the magi's desires.

(Base 3, +2 Metal, +1 Conc, +1 req., +4 constant, +5 maintains concentration)

Now the level lends credence to adding at least a +1 to the first effect. But since the device must effect itself, then we need to effect another target. But like A terem spell cannot effect you. So I'm inclined to throw proposal 2 out the window.

Now we have the multistage situation.

(1) Sense the motives of the (limb)
InMe 19
T: Ind D:Conc R: Touch

Senses the desired motion of the (limb)

Base 3, +1 conc, +1 touch, +5 Maintain, +4 constant

(2) Movement of the lost (limb)
ReTe 22 (27)
T: Ind D: Conc R:Per

Moves the (limb) according to the desires of Sense the motives of the (limb).

Base 3, +2 Metal, +1 conc, +3 Link Trigger, +5 Maintain, +4 constant, (for hand only: +1 precision)

This seems a bit shaky to me, but doable. Again, you need a ReIm spell to feel anything. The downside is the warping accumulation from constant effects in both case 1 and 3.


IMO, you need an InMe effect to detect the desires of the user, and a ReTe effect on a linked trigger to respond to those desires.

Also, if you're serious about doing this, I highly recommend SubRosa 14, as it discusses a Mystery Cult which does do body augmentation. There is a ritual that the mystery cult has that binds an item to the wearer, and they become one. I've only skimmed it, as I don't have a character who is really interested in this at the moment.

Sadly I don't have subrosa. But I was just questioning the statistics of a prosthetic limb. I'd assume a zombie limb would have the same statistics of a zombie, but what about a metal, stone, or wooden limb?

Well, let me preach about SubRosa. It's $4 per issue. Well worth the $4, IMO.

What are the statistics of a Zombie? :smiley:

Edit: fixed typo.

I don't see why enchantment 1 wouldn't work, but it would require 4 different arts to be around 10 to get the results, that's a bit of an investment. Quite a pain. The multiple step enchantment would be easier and you could outsource the other work. The real kicker is it is cheaper to make the prosthetic limb than regrow/reattach it with the first enchantment. 5 or 6 for the spell, 3 for the enchantment.

Zombie Statistics are in Hermetic Projects. This is on the idea that you make the limb, not harvest it. Harvesting from a dead donor would give you the donors stats.

"Created Zombie: (Str +3, Sta +3, Dex +1, Qui +0)" (Hermetic Projects 115)

Actually, "growing" (even an unnatural, e.g. a third eye) temporary, functional body part can be done with MuCo Base 5, with T:Part (Magi of Hermes, p.49). This can be a leg, or an arm, or even a pair of arms. A Hermetic prothesis would then be something like MuCo30 (Base 5, +1Touch, +1Conc, +1Part, +5levels item maintains Concentration, +5levels 24 uses/day). Note that it causes warping, so you don't want it to be always on!

Hm. The warping element might be a reason for having a prothetheic limb. For example, a stone arm might be simply considered a carried magical item, even if it was taking the place of a real arm. However, the InMe requisite to read the mind of the user might cause warping anyway. A way around that would be to have a verbal command. "raise cup to mouth" - although that might get old after a while.

Or, if a magi had sufficiently-high abilities in Medicine, chirurgy, or Artes Liberales, they could figure out via Natural Philosophy how the body transmits information down a limb - via tendons and whatnot - and have the talisman simply "feel" how the limb's stump moves, and act accordingly. (my theory is that a magical artifact has the same basic senses as a human being - and if a human can feel the tendons of another person move under the skin, then a magic item can as well) - but that might be a bit clumsy.

However, I personally don't know how Aristotillean physics/biology works, so I'll leave that up to someone who knows better than I.

...however, the warping suggests that such a limb might best be spec'ed as a Talisman. Very "eye/hand of Vecna" - and potentially an alternate version of the Criamon's body-talisman effect.

Hermetic magi could bypass the need for prosthetics (assuming that a flaw limits them from just re-growing the limb) by exploiting the familiar bond to either CrCo or MuCo a new limb. No warping, best prosthetic ever.

For everyone else, a point of warping a year is probably well worth having a functional limb.

Regarding warping, I read in several Ars books (for example Magi of Hermes) that if an effect was designed for a specific user in mind, he would not suffer from warping (ex p20 "His version is specifically designed for his wife, such that she does not gain Warping from this spell). Core rule book confirm that p 168 under powerful mystical effects.

Regarding the prosthetics, I would definitely consider three effects:
One to move the hand/leg (Re form depending on the material, with a base of 3 (if only attached) or 5 (if it can move without being supported - base on Corpus guideline), and probably +2/3 for fine motor control).
One to read the mind of the user (InMe30 as per core rulebook, p99 under Linked Trigger).
One to have feedback from the prosthetics (InIm base 1 (since it is only touch), use one sense at a distance, range: Touch (+1) or Arcane connection (+4) if you want to have an independant limb).
Duration for all of them should be permanent, so Conc +1, +4 maintain conc by the items.

Trying to combine all those three effects into one single spells to make a minor enchantment sounds too much of a stretch to me. Each of them have a very distinctive effect, not much in common with the others, even if at then end it is to achieve a common goal.

If the character has a flaw describing a missing limb or body part, the creo won't help as that will only bring the individual closer to their ideal, within the essential nature. So you're looking at muto in order to make what is essentially an unnatural change to someone with that affliction.

As standard, muto effects last a year maximum unless sustained somehow. Regardless, they are going to be considered a constant effect, which still inflicts warping whether designed for that individual or not.

A device helps overcome this but does require a couple of effects - one to provide motion under control of the wearer and one to provide touch/sensory feedback.

But, if the InMe effect is constant and necessary as I believe it to be, it is a constant effect and whether it was designed for the subject or not, he will still take warpiing of at least 1 per year for effects under 30th level.

True. It falls under the category of continuous effect. Customising the spell/enchant for one person specifically prevents warping from high level effect.

Also, I believe an InMe is required to have fast, instinctive moves.
If there is only an animation effet (Re Form) with concentration, it means that the owner of the limb must focus to make it act. Which means that the owner need to make Concentration roll as per p 82 of the core rulebook and will be hard pressed to do something else than focussing on its limb action.
Very likely, it won't be adequate for any fast-pace action (combat) or when multi-tasking is required (casting a spell for example: the magus must control his hand to match the spell gesture and focus on the spell casting itself - basically maintaining a spell and casting another one).
Having a InMe effect removes the need to consciously controlling the limb.

Aaand it will use Finesse... probably.