Thank you for playing! It's not a bug. Well, it depends. You get "knocked out" and *that* character shouldn't be able to attack anymore. After combat you are back at 1 HP. It's only if both characters get knocked out that you Game Over. If you happen to get knocked out to 0 and you level up during the combat, then your character will be at a higher HP than when you started. We're aware of the not being able to cancel out of the attack, but we realized it too late and couldn't adjust and verify that things weren't broken so that was left out.