Magical Sacrifice

Lagertha sacrifices for  the Great Heaten Army

In my games I generally don't shirk away from human sacrifice (or, since I'm running a campaign based around orcs, sapient sacrifice). Maybe I'm just weird and unethical, but when I imagine back to the willing sacrifices of the long-dead pagans I can't help but think of them as noble. They surrendered their lives so that, according to their worldview, the gods would not sunder the world or grant their families and their people safety and abundance. That's the sweet thing about sacrifice, especially in the pseudo-literary improv world of RPGs. So nobody thinks I'm a monster and despite it being obvious -- human sacrifice is bad and there were plenty of people that were sacrificed to gods against their will. In fact, after winning a battle, the Celts would sacrifice half of the enemy survivors to the gods in thanks for victory (how badass is that?).

In an RPG, however, sapient sacrifice can be awesome, or, as some put it, 'fucking metal'. I first started wondering how I would replicate or translate sapient sacrifice into the mechanics of the game when I was trying to prepare a fusion world of Celts and Vikings (using the Celtic Myth and Vikings supplements to help me figure it out). I then discovered the wonderful resource that is GURPS Thaumatology. I cannot recommend Thaumatology enough for the GURPS GMs who want to tinker with the magic systems of their worlds or attempt to find better ways to replicate magical worlds into GURPS. The Celtic-Viking fusion campaign never wound up taking off. Instead of making my won setting for that fusion, I realized I could just use Banestorm and elaborate the Nomad Lands. That didn't wind up taking off. So I decided, since I have Celtic and Viking parallels in the D&D setting, Lumaras, that I had made, why not just run the Celt-Viking campaigns from there. The only difference was that there were no Christians, which was both a shame and a relief. The mention of Christians in the rules below reflect that I had written them in preparation for a campaign involving Christians in the setting (Banestorm). So, using the Thaumatology toolbox, I came up with the following rule-set for the interaction of mana, the gods, and sapient, material, and animal sacrifice for my Lumaras GURPS Fantasy campaign "An Orc's Lot." References to GURPS Magic are abbreviated as M# (where # is the page number). I believe I didn't explicitly say that the energy from a sacrifice could be directed into a Powerstone for fears of unbalancing the game. But honestly, now I don't know whether it really would. Maybe comment below and weigh in on the non-controversy.

Orcs had practiced sacrificial magic for so long as any orc can remember. The orc gods often demand sacrifices, anyway. The practice of directing the sacrificial energy into Manastones is a practice imported from goblinkin mages.
Sacrifice works according to Thaumatology. Not only living sacrifices grant energy or ‘sway with the gods’. You can specifically ask the GM for an energy total when you perform a sacrifice after the sacrifice has been performed, and only for sacrifices which grant mana. You can perform sacrifices to empower spellwork or to ask for aid from the gods for a vague boon (such as “grant us victory against the Christians” or “let the winter be mild” or “fatten my pigs and let my harvest be bountiful”). These vague supplications will amount to various bonuses on relevant rolls or alterations in story or outcome.
The energy value of living sacrifices is based on intelligence and mass or health: for creatures of IQ 5 or less, it is equal to IQ multiplied by the lower of HT or HP; for creatures IQ 6+, it is equal to IQ multiplied by the higher of HT or HP. Certain aspects, such as beauty or purity (as interpreted by the entity to whom the sacrifice is sworn), provide a modifier to the total energy value. A willing sapient is worth twice it's typical energy value.
Sacrificial energy may be stored in Manastones (M70). Any quirks will generally relate to death, troubling emotions, and may cause inconveniences towards those who practice sacrificial magic (if any sacrificial victims were unwilling). These manastones are chalky in texture, have an otherworldly color, and, if examined, a foreboding and unnerving presence.
Finally, those sacrifices sworn to a deity as part of worship or broad supplication rather than magic do not grant energy; the energy is absorbed by the deity. Two examples: Sanktulo The Devout sacrifices Timmy (ST 9 IQ 10 HT 11, Willing +100%, young +50% for, unbeknownst to the player, 265 EP directly to the god) in honor of Grokolok, asking for survival through the winter or a victory against a rival tribe, or on a selected day to stay a hungry god’s wrath. Sorĉadanto the Arcanely Profane sacrifices Timothy (ST 10 DX 10 IQ 10 HT 11, HP 10 FP 11) to Kalgazgro or one of his agents for 110 Energy Points; he either transfers this energy in a manastone for later use (if he knows the spell) or uses it immediately to cast a powerful spell.