Thank you for the feedback! We understand that it's currently impossible to understand without an in-depth tutorial about the mechanics. The enemy's damage is actually consistent, but the reason it's unpredictable because:
1. We do not show their levels
2. There are actually 3 types of enemies, but we ran out of time!
3. There is actually a damage bonus for each enemy's die wins.
We will take a look about these problems after the game jam and hopefully improve the gameplay.