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

I've been trying it all evening yesterday and this morning. Ilfina is strengthening her troops with light magic, and I gave her the Berserker scroll. With the Berserker, a large part of the army is destroyed, but the strongest creatures still remain, and they are too tough for Agrila. Besides, in different attempts, I noticed that sometimes they stood near the wall for about 10 turns, and I could calmly destroy them with the Berserker, while in other attempts, they brought everyone out from behind the wall on the first or second turn. I don't understand this dependence, or maybe it's just a coincidence.
Well, I also think that it's better to gain a huge advantage (just skip a few days, and that's it:cool:).