- Attack Roll: High or better vs. armor and shield means a potentially fatal blow; no protection gives an advantage to the attacker, full plate metal protection gives an advantage to the defender; shields provide 1/3rd of the protection (either a follow-up roll for 1d6 combat or a 1-point protection value for shields in a 1d20/3d6 combat system, vs. 2 points for better armor than normal.)
- Saving Throw: High or better vs. extreme natural attacks or rays of light with unnatural effects; Extremely High or better vs. pure magic or powerful effects like dragon's breath; characters with classes get to modify the roll based on hit dice, and some classes modify saves against specific effects.
- Surprise Roll: High or better to surprise an opponent; rules mostly dwell on when not to roll surprise, or potential modifiers to surprise.
- Risks or Accidents Roll (drop hand-held item when surprised, spike slips): High or better means things change and the accident happens; can be modified by ability scores or preparations, of course.
- Hear Noise, Spot Hidden Enemy, etc.: Merged with the Surprise rules; no longer "skills", but allows characters to be forwarned (escape surprise.) Similarly, Open Doors is a roll to see if you force a door open with one swift kick, surprising any opponent; failure just means it takes longer and you negate surprise.
- Secret Door Roll: Merged with the Surprise rules; adventurers are considered "surprised" by the door and unable to notice it; if a monster uses the door to suddenly attack, the adventurers are automatically surprised; searching attempts to change that surprised state (High or better.)
Adding a modifier to the roll makes change more likely; adding it to the target number for a High result makes change less likely. If you have an advantage in a situation, you may add a bonus of +1 or more to either the die roll or the target number, whichever you choose, depending on whether you want things to change or not.Thoughts?