[Kristoffer O]

Initially (long before dom-ppp was released) magic gem use was optional and only a way of reducing fatigue. At this time sacrifice of slaves was optional and most blood spells were exhaustive enough to make sacrifice almost obligational.

I agree that self sacrifice (and HP loss) is thematic and sadly missing from the game. Not sure how viable it is atm. Most mechanics available in the game would probably be a bit ad hoc.