Herculean Body

Description (Cliffe)
Herculean Body, Passive Effect.

Herculean Body: This ability marks a new level of Endurance within its user. While this passive is active, the user may direct some of the power gained from his or her supernatural fortitude into their own strength.

The amount of power shared with the Strength stat is equal to 5% of the user's own Endurance, or more depending on the level of the ability.

Reference
Chuapter 64 "Overdue Explanations" (Cliffe)