Blood Magic is hardly a new concept to the fantasy genre, but how it is handled in Earthdawn is a unique approach to the subject. Typically, blood magic is portrayed as dangerous and negative, something that villains do and heroes may turn to as an option of last resort (most commonly as an aspect of martyrdom – a noble sacrifice, lesser of two evils, or ends justify the means).

In Earthdawn, Magic is a part of everyday life and blood magic is simply another kind of magic; not a wholly uncommon one at that. Everything must be powered somehow: common magic uses alchemy, true elements and other discrete things, though they tend to not be very powerful; spells and thread magic derive their power from the will of the caster being imposed on astral space, and as such this is only available to those specially trained to do this kind of magic; and blood magic is powered by your life essence. Every adept will engage in blood magic through Strain, perhaps frequently, while even non-adepts may make Blood Oaths or use Blood Charms.
There are a few kinds of blood magic that characters in Earthdawn will likely encounter: Blood Charms, Blood Oaths and Sacrifice Magic.

Blood Charms
Blood Charms are the fantasy equivalent of cyberware, and quite ingenious at that. Few adepts go without having some Blood Charm or another; Absorb Blow, Death Cheat and Garlen Stones being particularly common. Whether they help keep you alive, as with the previous examples, a bonus (Desperate Blow), or a new capability (Darksight Eye), they all come with a price: Blood Magic Damage.
This damage is the primary balancing factor when considering how many Blood Charms you want to load up on. Combat characters can handle more and are generally in need of more; they also tend to be more geared at that role. That being said, there really is something for everyone. The damage you take may be temporary if the Charm can be removed, or it may be permanent (generally the eye Charms), and may also require Strain to power it on top of the Blood Magic Damage. These Charms are not cheap, but can be exactly the thing you need to come out victorious (hence, Desperate Blow/Spell).
Any Group with a Nethermancer, Weaponsmith, or accomplished alchemist is going to have access to Blood Charms by simply making them. With even more time, they can also develop their own Blood Charms, which is awesome. The guidelines on doing that are broad, but straight-forward.
Some Thread Items may require this kind of blood magic for a deeper bond with their wielder. Those Deeds tend to be accompanied with a significant benefit of some kind, as well as signs of sentience from the Thread Item as it draws power not just from raw magic, but also from life and that connection. It always goes well.

Blood Oaths
Probably the 2nd most common form of blood magic to the denizens of Barsaive, Blood Oaths represent a very serious way to enforce behavior. They are also the foundation of an Adventuring Group. Whether they like it or not (depending on which end they find themselves), these are going to show up. There are three types of Blood Oaths: Blood Peace, Blood Promise and Blood Sworn.

Blood Peace is the Oath that most players will enact, since it is required to form an Adventuring Group. It’s pretty simply: not to hurt each other, or allow the other to come to harm through inaction. This isn’t one of those things where you can argue your way out of it; it is powered by your life and intent matters. The duration is for a year and a day, and if you come out the other side, you gain a +1 to your Death Rating (unless they are a part of your Group) and your scar turns gold or silver. Breaking this Blood Oath, like any Blood Oath, is bad business. Permanent damage and a Blood Wound. Those take a year and a day to heal, and generally give the impression that you aren’t to be trusted. The second part of the Oath is the truly dangerous part and this is not something to take lightly.

Blood Promise is generally the Oath that most players will find inflicted upon them. That being said, there is some upside for the dangers and 4 Blood Magic Damage: +1 to a Talent or skill for the duration (up to a year and a day). This is generally used to enforce some kind of behavior, such as not talking about an event, or performing a particular task. It can be an interesting way for two characters to help each other out in the joint creation of a magic item; trying to eke out every bonus they can (see Strain below).

Blood Sworn is the rarest Oath and one that I have only seen once, though also by far the most powerful. It is Blood Magic marriage, essentially, only without the necessity for romantic components. This Oath binds two Namegivers together for their lifetimes and the effects of breaking this Oath are very rough. The benefits to swearing it, however, are significant. It simply requires a level of trust and willingness to be together for the rest of your life that few without romantic leanings are going to undergo. The requirement of being loyal to each other for at least three years prior to the Oath remove any fears of Vegas-style Blood Sworn.

In most settings, obsidimen have a connection with the rest of their brotherhood that means any Blood Oaths they engage in apply to all of their brotherhood as well. Ergo, they are unwilling to take part in them. While this is an interesting bit of flavor (even appropriate), it presents a number of setting problems: how are they going to take part in a task where the employer requires them to swear a Blood Promise of secrecy? They may not be a part of an Adventuring Group (which is a thing). Therefore, in THIS setting, Obsidimen still have connection of sorts to their brotherhood, but as they have their own Name, and thus their own true pattern, they are as capable of using blood oaths as anyone without pulling their whole brotherhood along for the ride. Otherwise there would be no Obsidimen PCs.

Sacrifice
The most ubiquitous overall, this diverse category includes Strain, pushing Talents, ritual blood magic, Dying Act, Dying Curse, Dying Legacy and Dying Oaths. I know, diversity when four of the seven categories include “Dying” is questionable at best.

Strain and pushing Talents are common effects. The former is common even in the use of mundane skills in addition to Talents. The latter tends to show up the most when involved in activities that happen during downtime, such as Item History, Forge Weapon and crafting magic items. A +3 bonus for damage that can easily be healed over the course of a day is a strong benefit. The +7 bonus is significantly more problematic and I don’t believe I have had a player use that effect outside of combined with a Dying Act. Ritual blood magic is, usually the realm of plot – or a way to turn an otherwise healthy spellcaster into an unhealthy but very powerful mage.

Dying Act essentially allows you to dump all of your remaining Karma into a single roll, in return for dying afterwards. You may as well push your Talents while you are at it – you are already at the worst case scenario. Dying Curse allows you to, quite literally, get in the last word and screw someone over from beyond the grave. On the whole, this effect should be used sparingly from NPCs, but it is a fantastic way to have a recurring NPC go out. Dying Legacy is how many Legendary Thread Items are created and I have always considered it to be an additional element to a Dying Act (or Dying Curse, if that’s how they roll), rather than a one or the other situation. Dying Oath is almost always related to a plot; the dying character extracts an oath from another character to do something, and in return they get the dying character’s remaining Karma which may only be spent on all tasks related to the oath, even if you cannot normally spend Karma. You have a year and a day to complete the task and if you don’t, you cannot regain Karma for another year and a day. I would highly suggest that you intended to do this thing in the first place.

(Written by A.Cember, Edited for Campaign Consistency by G. Emore)