Sanctuary – “Life in death and death in life” [Campaign 4 – Mission 4]

Which spells belong to the original magic?

I asked about leadership because there are a lot of artifacts that increase leadership - hats, cloaks, etc. But what does it affect in battle or in the city - I still don't understand.
In Heroes 5, a hero with leadership received more troops while being in a city on a specific day of the week - either the first day or the last, I don't remember exactly.