To make a skill check, roll a d20 and add your character?s skill modifier for that particular skill. Compare the result to the Difficulty class (DC) for the task at hand. The DC may be determined by the skill?s description, set by the GM, or established by another character?s check result.
Unopposed checks: An unopposed skill check?s success depends only on your character?s action.
For example, climbing a chain to get out of a repulsorlift repair pit depends only on your character?s skill and luck, so the Climb check is compared to a target number provided by the skill?s description or set by the Gamemaster. If your result is equal to or higher than the DC, the attempt succeeds.
Opposed checks: An opposed check occurs when another character actively attempts to prevent your character from succeeding at a given task.
The DC for an opposed check is the check result of the character opposing your action. The opponent?s check might be made using the same skill you are using or a different skill, as defined in the description of the skill you are using. The character with the higher result succeeds at the action being performed, while the character with the lower result fails. In the case of a tie, roll the checks again until one character achieves a higher result than the other.
For example, if your character tries to hide from an opponent, your Hide check is opposed by the opponent?s Spot check. If your result is higher, your character successfully hides, and your opponent fails to spot him. If your result is lower, your opponent spots you, and your attempt to hide fails.