Frenzy Mastery on Ashe

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well, that can increase her attack speed by up to 15% max, correct? overall though, she loses a tremendous amount of damage because she can't take advantage of 250% crit damage instantly upon first item

her damage is still pretty high though

she takes full advantage of the 250% crit damage. the way the calculation works, just evens the crit damage out over all auto attacks instead of hitting hard for single attacks. the bonus crit damage factors into her passive aswell as the crit chance.

and yes. those 15% attack speed are pretty big early game. most carries can only make use of it latgame, when they attack fast enough with enough crit % to get the attack speed stacked up before it expires.