Worshipper – “Conquest” [Campaign 2, Mission 3]

For this mission, it is often advised not to capture the nearest castle, as the Druids produce units that the enemy quickly gathers. I had big problems, I used Arcomage on this mission, but then I came back to it and completed it normally.
I managed to quickly level up the hired elf hero, including in diplomacy, and charmed the neutral creatures from under the nose of the computer. :) Including the evil phoenixes. I wish the same for you.

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By the way, it is really difficult to find Druids!