Shadowverse

I had completely forgotten about this map. Did he play it somewhere in an unranked game?
Also, why wasn't it simply stated in the pre-nerf version that it "costs 1 less mana for each allied follower in play"? The descriptions in Heroes of Might and Magic are like that.

Added after 15 minutes
Oh, I understand, there was a bug in combination with the new cards. I should have checked the official website before asking. Well, at least they'll give out vials.