There are 3 Risk Levels. When asked, type in 7, 9, or 11. You have to get equal to that number or over it based on a random "dice roll" with 12 possibilities. 7 does 1 damage, 9 does 3, and 11 does 5. If you miss, you take damage equal to the Enemy Damage. If that's confusing, imagine you're rolling a 12-sided dice and the Risk Level is the number you're aiming for. If you get that number, it does damage based on the Risk Level. If you miss, the enemy hits you with the enemy damage.
I'm working on integrating this into a text based RPG. I know it looks horrible right now; this is just a showcase of the mechanics required to create my text-based idea. Inspired by the combat mechanics in Simon Tudhope's Choose Your Own Story: Shadow Chaser.