okay I saw my mistake now, you need to play militia and then feed them with apples to make them attack the enemy hero. plus the demon resource allows you to attack the enemy hero directly. pretty much everything else is card draw, resources gain, and trading resources. actually pretty fun game, got my interest once I figured it out. more fun than most other MMO card games on kong I've been playing.
I've noticed something interesting that level doesn't really matter in this game. I - a level 55 - have been beaten by level 40s in pvp and have beaten level 70s.