By the way, there are Azure Dragons near the castle, but there isn't that cage that was there at the beginning. Do you need to kill them using a force field?
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I don't think I'll have enough mana to deal with the Minotaurs.
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In general, an interesting feature of this map is that it's not easier to complete at a slow pace than at a fast pace. Some of the computer-controlled opponents are much easier to kill when they haven't left their castle yet or haven't been activated by a trigger.