In map legend there are eight groups of trolls. You can kill them with 3 successive blizzards.
It’s very difficult to pull this out at day.
I usually wait 'till night.
You make an archmage. Then get close to them. Then click "shift b" and then aim the blizzard. When you’re aiming, click the left mouse button 3 times.
Here is a catch; you must perform the triple click before you engage your enemy. Otherwise your mage will wait till he finish...
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