To champion a cause, one must be unflagging. Long marches and tremendous sieges require the inclusion of endurance training beyond that of any normal soldier in the skillset of a knight. Those with the fortitude of a champion will continually regain some of their vigor without resting. The vigor gained will typically be at a rate slower than resting, and can only go up to a warrior's natural resting vigor maximum, but the endurance advantage over long fights can be surprising.
Vigor regenerates up to resting max at a slower rate while not resting.
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