Okay, I lost once playing Moon, but it doesn't count because I already had a flying unit and decided to walk around instead, which was kind of funny, and then on the next turn, with 9 health, it cast Rune Blade 20/20 and got a buff.
Added 1 minute ago
I completed the story mode for the old Forestcraft with a terrible Forest deck (that I created when I started playing, right after opening the packs). The first two battles were easy, and I won the third one on the third try.

