Season 1, Episode 2B
-- When the PCs arrive at the monastery, they find all the monks subject to a worst disease (look like the bubonic plague), some of them already dead, the others agonizing and unable to move. This explains why the tank has not been resupplied. Of course, the PCs could also get the disease, despite it takes some time before they are totally incapacitated.
-- A monk explains to the PCs what happened: a group of bandits came two weeks ago; they needed some doctor for their leader who was ill. They took almost by force the three monks capable of miraculous healing and left for the hills. The problem was that the bandits were already carrying the disease and infected the monks who then couldn't cure themselves. Of course the monk asks the PCs to go and search for the missing monk healers.
-- Following the trail in the desert hills, the PCs arrive at the bandits' camp. It's an ancient prospectors' hamlet with a few crumbling houses and a small church. The church reeks of evil... Here is the hamlet's story: long ago a few prospectors settled there, and built a small church to thanks God when they found ghostrock. However, as soon as the church was finished, the prospectors wouldn't extract ghostrock anymore. They prayed to God over and over again, but to no avail as ghostrock was seemingly exhausted or well hidden. At last, in desperation and anger the prospectors decided to forfeit God and pray the Devil instead. The Church was converted to his worship, and the prospectors sold their souls to hell. More ghostrock was discovered thanks to the Devil, but the prospectors fought to the death to get it, and all died. Many years later a group of bandits discovered the place and decided to make it their base of operation. The bandit's leader eventually discovered the corpse of the last prospector who died guarding his ghostrock treasure. The corpse was rotten and moulded, and (probably thanks to the ghostrock effects) carried an horrible disease that the bandit caught.
-- When the PCs enter the place, the bandits are all dead except for a small number of them who are under a demonic possession. The three monks were unable to cure them, as the plague is supernatural and the bandits cursed by their own evil. So all the bandits died, except for those who accepted to host one of the dead prospectors' undead spirits in exchange for being cured of the plague. These demon-bandits are much more powerful than the hosts were prior to the possession. If exorcized, a possessed bandit returns to normal, but plagued and will soon die. If a possessed bandit is killed, the undead spirit will come out of the body (maybe attacking). The three monks are still alive and kept prisonners for some ulterior gruesome purpose. If they are freed, the monks will be able to heal the PCs, provided these are not tainted by evil.