@sactaphrax: we talked about it before because I am running a campaign that has "shadowlands taint" which is kind of like radiation poisoning...the longer you are exposed the more damage you take...and it causes mutations. I also had creatures that caused diseases that, if you get taken out by the disease, you turn into said creature. Your Wolf God disease would work very well for this, actually...
O.k...after re-reading your write-up ( I may have skimmed it the first time
)
I see that you have shifts of success/failure get added/subtracted. So when you gain enough shifts to bring the disease to 0, you're cured?
To simplify, why not set it up as an extended test. you need 'x' shifts to cure the disease.
Common cold:
Interval 1 day
Difficulty 3
Number of shifts required 5
Which I guess is kind of how you already have it. the symptoms would be based on the number of shifts left over at every interval....which doesn't really work...and it doesn't really simplify things at all...
What I like about an extended test is that it's a mechanic that already exists.
Which leads me to another idea:
You could say that the number of shifts left over(after each endurance roll) The disease makes an attack equal to the amount of shifts left over.
That attack can leave consequences. The worse you do on your endurance checks the more shifts the disease has and more likely to kill you/incapacitate/take you out. As you succeed, you the disease is less able to hurt you.
I actually like this. The numbers would have to be balanced. Fast acting, very deadly diseases would have high number of shifts, short intervals and high Difficulties.
Something not dangerous, but tenatious, like a cold, would have low shifts, medium difficulties and medium to long intervals.
Something that takes a long time to kill you, but is inevitably fatal (like cancer)would have High difficulty, long intervals but low to medium shifts.
Edit (again)
You don't get the cool Powers list that you drew up, though. (which I'm going to steal for my shadowlands taint). You only get to do consequences.