Mid Game+ magic.

[quantum_mechani]

archaeolept said:
mastema the heliophagus +4 blood = 8 bld which is enough for a demon lord.

also its B3 to start the booster path, or b2 + ring of sorcery, or B1 w/ rings of sorc and wizardry

hmm... I thought about double checking my numbers, but I was too lazy.

In any case, not everyone can have mastema, and there is the book of black secrets at b2 (which is obviously not always an option). It still boils down to blood being probably the most empowered path, however.