While looking over the Advanced Class Guide, one of my players and I stumbled across the Woad Painting Kit, an alchemical item that allows you to paint material components directly onto your flesh, as well as to create elaborate designs that allow you to cast a spell without needing it's Somatic components.
My player remarked: "Huh, that's a neat idea. I wonder if you could get something like this in a tattoo- that is, have a tattoo done for a specific spell so you can cast it without needing it's Somatic components."
I liked the idea, but I ran into two problems.
First, how much do I charge? To use the item to let you cast a stilled spell once costs 300 gp. I considered pricing it as a magic item that grants a feat (not unlike a slotless Metamagio Rod), but the effect would be permanent, but also restricted to one specific spell, and I wasn't sure how to best price that.
Also the question of how many such symbol tattoos (I like to think of them as 'spell circuitry') one could have. I don't think an unlimited amount would be broken, but if the item costs too much, the point would be rather moot.
If anyone else thinks this idea is neat, I'd love to hear your thoughts on how you'd price such a thing.
I don't know if this is helpful or not, but for the Kaidan setting of Japanese horror (PFRPG) there is a tattoist wizard archetype called the Horimyo (arcane tattooist). This archetype is from our Way of the Yakuza class/faction guide supplement. Since this is a class feature rather than an alchemical item, it might be less helpful than I'd like to be able to offer as a suggestion. Insure to read the linked descriptions for related feats used by this archetype. Basically, creating spell tattoos is equivalent to creating a scroll, plus 50 gp for cost of ink and supplies.
As mentioned in my post creating tattoos at least by 3PP development is not a permanent effect, it only stores one use. Once used the tattoo disappears, so it works like a scroll. There are also wondrous tattoos that are permanent, but they in all ways works as a typical wondrous item. Wondrous tattoos cost the same as normal wondrous item creation plus 100 gp in inks and supplies. Wondrous tattoos that don't take up a magic item slot cost twice as much.
Here's a couple specific Wondrous tattoos:
Hidden Sword
Aura moderate conjuration; CL 9th
Slot 1 hand; Price 3,000 gp plus cost of weapon;
Weight -
Description
This tattoo is most often rendered with the image of a weapon on the inside wrist of the user. To create this tattoo, the spellcaster needs access to an actual weapon, and the weapon is then melded to the tattoo,
so that it is carried, weightlessly, in the tattoo. A weapon carried in this way may be “drawn” as a free action and “sheathed” at will within the tattoo. Once the weapon for the tattoo is chosen, it cannot be
changed without dispelling the tattoo first, though a different weapon can be “sheathed” in this way on each arm and additional weapons can be added to the same hand for twice the cost of the original tattoo.
Construction
Requirements Craft Wondrous Tattoo, secret chest;
Cost 1,500 gp plus cost of weapon
Mistwalker
Aura moderate transmutation; CL 5th
Slot Back/Cloak; Price 15,000 gp; Weight -
Description
This tattoo is most often rendered with the large image of a woman, the bottom half of which is misty and ghost-like, inked onto the back of the user. Twice a day, the user can cause their form to shift and waver
for 5 minutes , as with blur. Once per day the user can assume a gaseous form for five minutes.
Construction
Requirements Craft Wondrous Tattoo, blur,
gaseous form; Cost 7,500 gp
It sounds a lot like the "Eschew Materials" feat, in tattoo form. What is the maximum gold piece value you wish to be available?
Edit: add "before taking into account the still spell aspect" before the question mark.
I appreciate the replies- I'm still on the fence about this. Maybe it is a bit much of a benefit for a mere gp cost. I'm considering a feat or maybe, if I feel ambitious, a prestige class or archetype based around casting spells worn on one's body.
I'm pretty sure there is a sorcerer archetype and some feats that deal with tattoo magic in the Inner Sea Magic book. Which is a pretty awesome book by the way.
If you use Spell point system or some other type of spontaneous casting then the tattoo could just be added to the spells known, the caster pays the cost (in sp/mp/whatever) each time they use the spell stored in the tattoo... Even if you don't use such a system you could let them sacrifice a spell for the tattoo spell like cleric can for heal spells. A feat to learn how to use them would be appropriate; not having it could give a chance of spell failure, 5% per level maybe? A character could get a tattoo and then role play learning how to use it for a level or 2 before getting the feat. I would limit to 1 (maybe 2 for arms) per limb, 1 on the head, 1 on the back and 1 on chest. Each would have to be thematically correct for that slot so Fly spells would have to be on the arms or back.