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I'm playing the campaign as Necromancers and I've encountered a problem... In the second mission, when the Necromancy bar in battle fills to more than 50% and advances to the second level of the Necromancy skill, I can't use it. However, the first level works fine... Can you suggest what I might need to upgrade on my hero?
http://radikal.ru/F/s019.radikal.ru/i625/1209/a5/5a8f490e45e4.jpg.html
http://radikal.ru/F/s017.radikal.ru/i401/1209/98/3895da928b68.jpg.html
As you can see in the second screenshot, it's my turn, but the Necromancy ability is inactive. Because of this, I'm suffering heavy losses.