I have done a lot of Nurgle, but finally reached the "this is a complete force" point and can take a break. The Black Templar hype is real, but I know for a fact that the converted Librarian won't be wearing the black of a Knight of Sigismund. I often just go with the flow when it comes to one-offs who have some part of the paint scheme that is different from the rest of the army, so not as many pictures of the process.
Kantor Blue base, mixed in some Phalanx Yellow for the next layer. I heard that using a warm color to bring up the hue of a cold color can improve contrast.
Then worked up the blue to lighter hues by using Macragge Blue, followed by Macragge Blue/Hoeth Blue, then Alaitoc Blue/Hoeth Blue with the idea that working in the colder Hoeth Blue would add contrast to the Kantor Blue/Phalanx Yellow layer.
This is my first time painting up significant portions of a mini without using washes and shades in quite a while, but I'm pleased with the result.