1st offline tournament

Dear users, I have a small question...
So, does it mean that a necromancer hero
cannot use their skill?
If demonology is not necromancy, then what
is it? I remember that there was no such skill
in the 3rd game.

Demonology is about accumulating a large stack of demons, "reforged" from other troops using the special ability of Pit Lords (the 5th upgraded monster in Inferno).
Sometimes, necromancy also has restrictions, but there are none in the first turn of Might and Magic I – please use it. :)