Outcast's Path

Reinforcements should work in any case, unless you kill everyone. By this time, you have Phantom Summoning, Berserk, Blind, etc., in your arsenal, regardless of the school of magic. Why not win even with a large army, although your army will grow to be quite large; the main thing is not to waste resources unnecessarily.

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I'll reduce his defense now.

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But I'll only do this on Medium and Easy difficulty.

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Done =) Vadim_t, even taking into account the purchase of buildings, you missed one more quest somewhere.

1) Out of the potential reinforcements, I only killed the army that was besieging the human garrison. Now I'll try to avoid this and buy buildings from the humans. The fighters near the purple key and those asking to eliminate the druids guaranteed reinforcements.
Blind and Berserk don't work on Laslo; Phantom will be shot down immediately if I don't cast Dispel first. The only option is to accumulate a very large army (so that it doesn't destroy the entire stack, but at least half of it) and use Vampirism as much as possible. I played very carefully and lost a total of about 100+ units, mostly scouts. In addition, I captured the Castle and dwellings as quickly as possible; in the Castle, I used the altar - Beasts +7, and a heroine with the Leadership Crown and the corresponding perk was stationed there. So, the army was at its maximum (I didn't take any enemy units); to increase it, I just had to wait.
2) The only potentially missed quest is to kill the human army. But it wasn't given to me. Since there are no attachments in the private message, I'll make a list here (some of the quests completed for the humans and elves are missing).