Any ideas on how to force a computer-controlled hero to cast Clone? From my experience, the computer casts Clone when it feels its army is much stronger than yours. However, in such cases, the computer usually prioritizes summoning elementals.
It's best to choose heroes with the weakest stats and smallest armies, as they know all the necessary spells. I learned almost all the magic on the blue computer: Resurrect from Gundula, and Clone and Prayer from Gretchen, i.e., the weakest heroes.
Resurrect is cast when the computer feels it can win by reviving its forces. If you have a huge advantage, the computer will use offensive magic, ignoring resurrection.
It casts Prayer when there are many units (especially under Slow), or when there are many low-level units (level 1 and 2), as it significantly increases their stats.
However, the computer casts Clone from time to time. In my specific case, I lured the hero onto land from a boat and attacked him. He had 2,000 Hot Goblins and about 2,000 Orcish Warlords. He cast Clone on his archers, so I simply positioned my archers and another unit in front of them to take the direct hit, and then he cast Clone, as this would inflict maximum damage. I had to endure it for the sake of the Clone :) In the same battle, the computer cast Mass Prayer, as the Hot Goblins and Orcish Warlords were under Slow, and Prayer increases their stats. At the same time, the armies should be somewhat comparable; otherwise, the computer may panic and only cast offensive magic. Clone is often cast on archers.
If you have already killed all the blue heroes and don't want to retreat, you can wait for another computer (e.g., a Swamp creature) to leave a suitable army on the hero. You can time this. Check in the editor or prospector who knows Clone and catch these heroes with Dessa.
P.S. The current update is such that on this map, I have already killed the blue and gray (Necropolis) heroes. I took the Grail and placed it in Flax (but I didn't get Flight or Teleport! :) but I did get Force Field, without which I think it would have been impossible to kill Tanta in the field (and in defense in the castle, it's quite possible even without Force Field). I control almost the entire map, and I have already taken all the tents, including the black one. The interesting thing is that the development has not gone according to the scenario: some of the computer heroes have fled to the water and fire lands and stayed there, and they are not opening Guardians. And I can free Gervulf and Brochilde on the Swamp respawn and take them into my army (although this shouldn't be possible, as some Guardians won't open). Nevertheless, the map is nearing completion. I will not have to kill Tazik but can let him die by capturing all the castles, and I plan to kill Nelka and Mephala with magic (redeemed mage heroes). It also looks good to capture the Tavern and redeem the killed Crag Hack 6424 level :)
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Did you play through HotA? :)
