Leveling up from 1 to 12 as an necromancer human - close to FREEPORT

[Jimjam]

For the hot blood series the highest level spell (cast by the highest level necromancer) takes priority.

For the disease line they all stack. I forgot how/whether the poison line stacks. My inkling is they do?

If working with another necromancer you need to coordinate your spells with each other - you can't stack the same spell cast by multiple casters. E.g. if 5 necromancers cast disease cloud on a mob, only one copy of the spell will stick (the one cast by the highest level necromancer, which overwrites/blocks previous/future lower level casts).