Nagash’s landmarks generates constant corruption
This mod changes the landmarks related to Nagash (the Black Pyramid itself + Nagashizzar) to generate constant corruption no matter what, even when they are destroyed (just a small amount, but it will linger. It’s a "legacy" thing).
I also altered the Black Tower of Arkhan to generate vampiric corruption, but not as strong if compared to Nagash’s. Arkhan can unleash more corruption if compared to vampires or Azhag for "lore" reasons.