As originally advertised, Vengeance was supposed to cap at 10% of our max health; but no one was reporting reaching this cap, so it has been widely assumed that stacking stamina to increase the Vengeance cap would have no effect on threat, or in the case of bears, Savage Defense. If we weren’t reaching the Vengeance cap at our current levels of stamina, adding more would be a waste!
Well, it turns out that Vengeance is not linked to max health after all, because the underlying mechanics of Vengeance were not implemented as advertised. Instead of being based on health, Vengeance scales at a 1:1 ratio with stamina. (It also has a small contribution from base health, but base health cannot be modified, so there’s no scaling – just a tiny bit of naked vengeance). Word from the blues is that this is intended, and that Savage Defense is balanced around this lower Vengeance value.