Originally the Scourge's plan was to infect the water supplies of Lordaeron to transform the populace into undead. The problem was giving a single unit the power to infect water with the plauge made them very difficult to mask as living. So the Scourge was forced to resort to infecting grain. Which did not require an undead agent to be present at the infecting site.
I made a discoverey, This skin looks awsome when you make the clothes black!
undead, water, plauge, infect, death, medivh, dead, magic, taint