I would like to know which faction (besides other Necromancers :)), in your opinion, is the most difficult for Necromancers to fight against in a game of average length, on a "large" map (Hero level 20+)?
In my opinion, it's the Light Elves, because they can easily learn Light magic, have a fast development, and strong units, and can also choose three Necromancer units as their sworn enemies. The Hero is Ossir (I think everyone knows about his advantages).
The thing is, I'm going to have a battle with a Necromancer soon, and I don't want to lose. The opponent's Hero will most likely be Kaspar. There will also be 3 AI opponents.
Please, clarify on which week you are expecting to encounter the opponent.
By "average game," I mean the final stage on weeks 4-6.
In this case, it's best to choose the Tower faction and the Hero Vaishan.
If you mean a later stage by "average game," then the question arises: how rich is the map in money and resources?
If the map is rich in money, then Humans with training will help you.
If it's rich in resources, then Dwarves with runes and Eternal Light.
If there is no particular abundance, then Light Elves.
Творят настолько черные дела,
Что до таких блистательных идей
Не вдруг дойдет и записной Злодей
Темный адепт клана GODS