[Taqwus]

The 'death' route is to avoid the slow accumulation of many afflictions by dying first. Consider teleporting into a water province, drowning (Baphomet isn't amphibious, is it?) and hopefully not picking up much. Then Call God to bring him back. Waiting for the disease to kill him will still kill him, but with many more afflictions on the way.

Otherwise, without nature, and being Marignon -- since you can't forge the Chalice (takes N/S IIRC); can't cast GoH (N5); can't summon Fairy Queens; there are no mercenaries who can heal; and don't get any national heroes or commanders that can heal troops; you need to enslave a healer from a nation that actually gets them if you remain completely without nature.

You might be able to -get- nature magic, 'tho. Conquer a province with Druids (N1H1), certain tribesmen (Jaguar Tribe priest-mages have N1 guaranteed and need no magic site unlike, say, Witches where you have a bootstrap problem), hire the Boar Mage mercenary, or alchemize. It'll still be expensive to work up to the point where one can cast GoH, summon a Faerie Court, or build the Chalice.