I know I could do all the research myself but I thought this would be a fun post and something people could get creative with.
Here is the idea. Evil Villain (called Evie from now on) has a plan. She wants to infect rats with a horrible plague and then use the rats to infect the people and get the people to infect each other. This will bring the kingdom to its knees without Evie ever being in danger.
The biggest problem Evie can see is priest curing the sick so she has to be able to target clerics first. Get rid of the sources of magical healing and the plague becomes much scarier.
Evie is prepared to invest in her grand scheme so can research new spells, lets give her 2 years (104 weeks) to complete any spell research.
What profession would have the spells needed? What is the lowest level that Evie could be to pull this off? Is a ritual to cast the 50th level Plague on a rat and then 9th level Animal Mastery to get that rat to just nibble on hundreds of other captured rats ( you could pay peasants a tin per rat to bring you live rats so that would not be a barrier). This would give you an army of plague carriers. Further castings of Animal Mastery could be used to target clerics.
I wrote the top half last night and was then thinking about Evie and had a second idea below.
Playing wound with 50th level rituals is fairly dangerous but there is another way and this is far more horrific.
Evie buys a few hundred live rats for a bronze piece. She kills one and then on the fresh corpse she creates and controls a type 1 undead. Not a zombie or a skeleton, no, she goes for a Lesser Ghoul. This bit is a bit rules fuzzy, Ghouls are not standard created undead but a bit of narrative dark rituals and maybe trading with shady dealers in necromantic antiquities and Evie could get hold of a part of a ghoul that could be regenerated into a ghoul.
With her captive ghoul she infects the captured rats with Ghoul Rot and Bubonic plague (See Creatures & Treasures or Creatures & Monsters and even Creature Law).
This is a much easier way of getting plague infected rats.
Control Undead will work on ghouls just as effectively as created undead so we are only looking at 2nd level for Control Undead I.
If the dealer in necromantic antiquities only had greater ghoul parts available then they are Type II so a 6th level Control spell is needed.
Evie could then control a single rat ghoul and send it into a church with the intention of ‘touching’ as many people as possible. No attack is actually necessary just their touch. The disease attack is not very high so not everyone is going to become a ghoul (30% chance on a fail) or get the plague or gangrene. Ideally Evie will get into the church during a service when there would be several clerics present and then send her rat running around and try and infect as many clergy and lay clergy as possible before having the rat running over the feet of the congregation.
Statistically about 1 in 5 normal people who are touched by the rat will become infected by Ghoul Rot and 2 in 5 will get gangrene or the plague.
This is a repeatable exercise if crowds gather to beseech the clerics to treat the plague victims that is a place to release a controlled rat ghoul.
The plague is contagious as is Ghoul Rot. In three or four days you have epidemic levels of undead infestation and disease.
Could the available clerics, that would need to have the Repulsions list, deal with the exponential growth in undead? That is on top of the growing tides of plague victims and those suffering from gangrene.
At this point I am thinking of the impact of releasing one controlled ghoul rat at a time to target the clerics in a community. Imagine if that evening Evie released a hundred plague and ghoul rot infected rats into the dock district or a towns warehouse district. You average barn contains hundreds of rats that will soon be infected or become carriers.
In a city a hundred rats into a sewer system could spread Ghoul Rot and plague right across the city in three days.
The speed and scale of Evie’s plan is limited only by power points. If she is around second level then although she can cast the control spell she only gets two or three castings a day barring any spell adder or multiplier. In RMSS the power point count is much higher and she could attack multiple temples and churches in a single day.
In RMu she could concentrate on multiple rats meaning she could achieve more in a shorter time. If she picked her moment to coniside with a major public religious festival she could get much greater access to high ranking clerics.
The chance of infecting a high level cleric is slim but there is always the chance of one or some failing their resistance rolls. If you picked a day towards the end of the festivities any visiting clerics could be infected and then take the infection away with them as they disperse but before the nature of the disease is obvious. That would make it harder to find and cure the possibly infected clerics quickly and make sure you got all of them.
Whilst the plan is not foolproof it is easily repeatable and if Evie has Control Undead, Repulsions and Cure Disease she is pretty much proof against her plans turning against her.
This is my take on how Evie could bring a kingdom to its knees and it looks like 6th level would be more than adequate to have the lists, spells and power points to carry it off.
Any better ideas?