Run feat with no constitution score?

[fableblade]

How do you use the run feat when you have no constitution score, you can run 5 times your normal speed but to keep it up you must make a con roll, What do you use in it's place?

 

[Alzrius]

From the SRD regarding Nonabilities (emphasis mine):

Constitution

Any living creature has at least 1 point of Constitution. A creature with no Constitution has no body or no metabolism. It is immune to any effect that requires a Fortitude save unless the effect works on objects or is harmless. The creature is also immune to ability damage, ability drain, and energy drain, and automatically fails Constitution checks. A creature with no Constitution cannot tire and thus can run indefinitely without tiring (unless the creature’s description says it cannot run).

 

[fableblade]

Thank You.