Stamina

Typically used with: Endurance.

In short: tough it out. The Stamina skill is used when a character is performing strenuous activity. Many environmental effects require a Stamina check to shrug off, such as extreme heat, cold, thin air, or no air. Survivalists, backpackers, and free-divers would make heavy use of the Stamina skill. Any time you're trying to push your body past its natural endurance limits will call for a Stamina check.

In general, if you're trying to avoid moving down the Knockout Track, increased Stamina is your best defense.

Difficulty

The DL for environmental effects is extremely varied. In general, it should be based on the extremity of the climate. Your GM has the final call, as always, for determining DL for these.

If a character is suffering from environmental effects (heat, cold, etc.) and fails a check, he moves down one step on the Knockout Track. Each hour a character is in a harsh environ, a new roll must be made.

In an environment with no air, a character who is not doing anything physically taxing can hold her breath one minute for each point of Endurance she possesses. After this, the character is considered to be suffocating. For each round spent suffocating, a Stamina roll against a DL of 15 must be made in order to keep from slipping one step down the Knockout Track. Each round the difficulty increases by one point (DL 16, DL 17, and so on). Once the character reaches step five (unconscious), if the suffocating conditions persist another round, the character suffocates. One skilled in Healing may be able to revive a drowned character if quick to action.