Fenador

Recently I've been seeing some of the end-game tanks stack their Shield Block rating into the thirty percentie and showing no sign of stopping. My question is, why so high? I understand that 25% must be achieved to maintain 100% block why the buff is up, bu beyondhat it seems like all they're doing is stacking it incase of 1 of 2 scenarios, either they're taking multiple mobs that can easily get through the buff charges, or 1 quick hitting mob that can get through the charges. When the block buff isn't up, wouldn't Dodge/Parry serve the same purpose as block, with of course the added benefit of not taking any damage, or is this some sort of rage generating mechanic?