Thanks for playing! I definitely agree that there's a lot to improve with making the rules clearer, definitely something to revisit.
Basically the way the health mechanic works is that, during the defense turn, you have to match the attack points you've set up in the attack turn. For example, if you play one card with 4 attack, you'll need to play a card with 4 defense (or lower, but you'll lose health).
I hope that makes sense lol 🙏 Glad you enjoyed it overall!