Binding Oath

This spell allows up to four creatures, one of which can be the caster, to make an oath or a promise which they must keep under penalty of death. Each of the creatures who are participating in this spell must be able to speak and understand the same language, must be able to completely understand what they are promising to do, and cannot be under any sort of compulsion or charm effect. If everyone involved does not agree, does not understand, or is not acting of their own free will, the spell fails. 

On a successful casting of this spell all the participants make the same promise or oath, to do, or not do something, which must be possible for them to accomplish or avoid. The spell places a small mark on their body which cannot be removed. 

Should at any point after the spell is cast any of the participants intentionally break their promise they instantly die. Should they be brought back to life the spell is not broken and they will die again should they continue to fail to live up to their oath.

The spell only ends if the conditions of the promise or oath are fulfilled or negated and it is no longer possible to maintain the promise. At which point the spell ends and the mark fades away. (I promise that I will keep this person from being killed until they reach their home. Once they get home alive the binding oath ends, or if the person dies before they get home the binding oath also ends, but may also kill the one who promised to keep them alive, depending on why they died.)

If a creature under the effects of this spell is afflicted by a charm effect, and under the effects of the charm they are asked to break their oath or promise, the charm effect is instantly dispelled, and they regain their free will.