7.11 Endurance (Con)
The Endurance skill represents your ability to persevere through physical trials.
7.11.1 Common Endurance Tasks
Hold Breath: You can make an Endurance check to hold your breath. While holding your breath, you must make an Endurance check at the end of every 5 rounds that you spend without taking any actions, or at the end of any round in which you take an action. The difficulty value starts at 0, and increases by 1 for each subsequent check until you breathe in air. Failure means that you try to breathe in air, and you gain a vital wound if there is no air available to breathe.
Essentially, you can fight while holding your breath for a number of rounds equal to your Endurance modifier with no risk of failure. If you stay still, you can hold your breath for a number of minutes equal to half your Endurance modifier with no risk of failure.
Maintain Exertion: Some activities are difficult to maintain indefinitely. For example, sprinting typically exhausts a creature in a minute or less. Even walking at a steady pace can become exhausting after hours without rest. You can make an Endurance check to continue performing a strenuous activity without rest.
Generally, this requires a difficulty value 10 Endurance check when you have performed the task for as long as a normal human can do it without rest. Each time you succeed at this check, you can maintain the exertion for half that length of time. At the end of that time, you must repeat this check to continue the activity, but the difficulty value increases by 5. If you fail the check, you must rest. The details of how long you have to rest depends on the activity you were performing, at the GM’s discretion.
For example, a human can normally sprint for 10 rounds without rest. If they pass a DV 10 Endurance check, they could sprint for an additional 5 rounds. After that time, they would need to make a DV 15 Endurance check for the next 5 rounds, then DV 20, and so on.
Overland Exertion: You can make an Endurance check while travelling overland to cover more round (see Overland Movement). This is a special use of the Maintain Exertion ability described in the core rulebook. There are two ways that you can exert yourself: hustling, which doubles your distance travelled during a given hour, and making a forced march, which allows you to travel for an extra hour beyond the normal travel time. Making a forced march only increases the difficulty value of the check by 2 for each additional hour, instead of the normal 5.
Stay Awake: You can make an Endurance check to stay awake beyond healthy limits. A typical creature needs a minimum of 6 hours of sleep for every 18 hours spent awake, and a minimum of 50 hours of sleep every week. The difficulty value starts at 5, and increases by 5 for each subsequent check until you catch up on your missed sleep. Failure means you increase your fatigue level by three. You must make another check every 8 hours as long as you are still beyond your normal sleep limits.