If an adversary has advantage on an action roll, the GM rolls an extra d20 and counts only the higher result. If an adversary has disadvantage on an action roll, the GM rolls an extra d20 and counts only the lower result.
Adversary Advantage & Disadvantage
If an adversary has advantage on an action roll, the GM rolls an extra d20 and counts only the higher result. If an adversary has disadvantage on an action roll, the GM rolls an extra d20 and counts only the lower result.