What's the price of blood?

Question

The class Tainted Sorcerer from Unearthed Arcana (p. 191) has, among other abilities, the class feature "Blood Component":

Blood Component

A tainted sorcerer must use blood in place of any spell's material component (if the spell has no material component, ignore this cost). [...]

Meanwhile, the Eschew Materials feat states:

Benefit

You can cast any spell that has a material component costing 1 gp or less without needing that component.

So, is there information on how much (normal, say human or pig) blood costs in any setting, Greyhawk, Faerûn, Eberron or whatever? Can a Tainted Sorcerer get rid of the gruesome part of the Blood Component class feature by getting Eschew Materials, or is blood too expensive?

Answer 1

Packaged blood won't work here

Tainted Sorcerer says:

She has two choices for a source of blood: herself or someone else.

If she uses her own blood, the minor knife cut to draw the requisite blood is a free action that becomes a normal part of casting the spell. (...)

If the tainted sorcerer draws someone else’s blood to use as a material component, the rules given above generally apply.

The blood must be obtained freshly by cutting a creature as part of casting the spell. So packaged blood as a good that the feat applies to won't work.

You however could still power your spells by blood you bought, if you lugged around a proverbial sacrificial lamb.

Blood prices would depend on the kind of blood

Even when blood is not listed in the equipment list, you can buy blood by buying livestock (listed on the trade good table, or on the table for mounts). This also has the advantage that if you bring the creature along, you can use it as a source of blood for your tainted magic. The price would depend on the animal.

For example, a goat costs 1 gp, and has about 3.15 liters of blood, about 0.8 gallons so goat blood would cost you roughly 1 gp 2 sp per gallon. As the cost is measured in hp, not gallons, a goat has on average 5 hp, so a cost of 2 sp/hp.

A pig costs 3 gp, and has about 7.15 liters of blood, costing you about 1 gp 5 sp per gallon, with an average of 6 hp, of 5 sp/hp.

Human or elf blood may not be available to purchase this way, or at least would be evil or illegal in campaigns that encompass slave trade or human trafficking. Thanks to @From, I can report that "Slaves are costly (a young human field slave sells for about 50 gp in the markets at Eltabbar), so few commoners have the means to own them." - Unapproachable East, p. 159. A human would have up to 1.5 gallons of blood, for more than 33 gp per gallon, and a first level commoner has a d4 hit points, so on average 20 gp/hp.

Answer 2

Blood has no listed price

If I'm reading the rules correctly, the amount of blood that you would need depends on the price of the component; it could be "1hp worth of blood", "5hp worth of blood", or even more than that. There is no market price that corresponds to this. When a material component has no listed price, Eschew Materials does not apply.

---

You can still apply Eschew Materials to spells with cheap material components, which will prevent you from needing to lose the 1hp that you would otherwise lose.

The blood costs of the tainted sorcerer are measured in hit points (not in gallons), so talking about a "price per gallon of blood" is not meaningful for this purpose.

Answer 3

A Tainted Sorcerer with Eschew Materials does not need blood for spells with a material component costing 1 gp or less

The Blood Component class feature and the feat Eschew Materials both affect the use/need of material components for the caster, but it makes a difference what you apply first: replace a spell's material component with the appropriate amount of blood or remove a spell's material component if it’s price is 1 gp or less.

If you you follow the faq guideline „whenever the rules don't stipulate an order of operations for special effects (such as spells or special abilities), you should apply them in the order that's most beneficial to the creature“, you should apply Eschew Materials first.

Eschew Materials says you don’t need material components costing 1 gp or less. If no material component is needed, the spell (for you as a caster) effectively has no material component and the Tainted Sorcerer can simply ignore the blood cost.

Consequently, the Tainted Sorcerer wouldn’t have to worry about blood market prices at all...

Answer 4

It's 'free'.

The cost for a Tainted Sorceror's Blood Component ability is measured in Hit Points, not Gold Pieces. No cost for the blood is mentioned anywhere within the ability.

This means that it costs less than a single GP, and therefore that a Tainted Sorceror with Eschew Materials doesn't need to pay for spell components at all.

Given the drawbacks of the class (casting using your Taint score rather than your ability modifier, needing a minimum taint score to cast spells, needing to make a Will save vs your Taint score every time you level up to avoid wasting a level on a class with no abilities other than spellcasting, making a save to avoid taking Taint every time you cast a spell until you hit 0 Wisdom and go comatose), this honestly doesn't seem that bad to me. It's strong, but not that much stronger than all of the other things you could be doing as a full caster.