Persons so skilled in this proficiency have the ability to temporarily exceed normal running speed limits. For each slot invested, the runner can exceed normal racial limits by 1// per round; enhanced speed can be maintained without penalty for one round per point of Endurance. After the initial period is expired, an Endurance check must be made each round with a progressively cumulative -1 penalty to Endurance. This penalty is not against the die rolls -- actual Endurance is expended each round. Constructs may not take this skill, due to the fact that their maximum ground speed is fixed.
Critical Success: The character can run for a 50% greater time before Endurance loss begins.
Critical Fumble: The character stumbles, and gets muscle cramp that precludes running for 1d4 rounds.