Haven – "Everything is mixed up, truth and falsehood" [Campaign 3 – Mission 2]

The main hero is limited to level 17, but there are so many points on the map that you could gain a few more levels.

I agree, I played on hard difficulty, and I had neutral stacks of 500 or more, so I think you could easily level up to at least level 20. Anton can complete the map without losses as a Blood Warrior, because the perks you can choose along the Blood path are really great. And to avoid losses, of course, use Reinforce 1, 2, and Healing. That's always been my tactic. At the beginning of the turn, I could make the main creature stack invulnerable for one turn thanks to the unique alliance building in the city. I would cast invulnerability on the Vestal and, when someone was injured, I wouldn't rush to heal them immediately, but just wait, because if you move right away, the invulnerability will disappear. So, invulnerability on the Vestal, Reinforce on the Archers, and the computer usually starts attacking the Griffins, which we then restore with the Vestals. Oh yes, another important point: upgrade Tactics and arrange the stacks so that the Vestals, Archers, Luminaries, and Knights stand close to the defenders; then they will absorb some of the damage, which has saved me many times. And in general, that's it; you can easily clear the entire map in this way without losses, or with minimal losses.
P.S. There was also an interesting moment: I discovered a hidden area of the map using the alliance building. On a ledge on a cliff, there was a small campfire; I thought I would find an Easter egg, but I didn't see anything.

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