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Basic attacking an enemy champion grants 75% - 125% (based on level) bonus attack speed for your next 3 basic attacks. While active, Hails of Blade removes the attack speed cap.
Hail of Blades lasts 2 seconds, and each basic attack refreshes the duration to 2 seconds.
Cooldown: 4 seconds out of combat.
Out of combat cooldown decreased. Maximum time between attacks increased.
Hail of Blades isn't a top keystone for any champion right now. We're lowering its cooldown to up its potency on champions who prefer staggered, short trades.
OUT OF COMBAT COOLDOWN :  ⇒ 4 seconds
MAXIMUM TIME BETWEEN ATTACKS : [1.5] ⇒ 2 seconds
We're still watching players experiment with Hail of Blades on different champs and builds. Its list of users is turning out to be narrower than expected, but its underwhelming power level isn't doing much to encourage players to experiment. We're giving it a booster shot for now and will evaluate potential mechanical shifts based on the results.
BONUS ATTACK SPEED : [50-100%] ⇒ 75-125%
One of the goals of runes is to give champions options about what tree they go into based on how they want to play. Domination is a tree about burst, which should make it appealing to some of the burstier marksmen, but there is no real keystone for them. Hail of Blades should help spell-based marksmen who want to lay down a swift chunk have a keystone to promote that playstyle.
HAIL OF BLADES : Gain 50-100% (at levels 1-18) attack speed for the first three attacks made against enemy champions.
NOW NOT LATER : If more than 1.5 seconds elapses between attacks this effect will end
CANT STOP WONT STOP : Hail of Blades allows you to temporarily exceed the attack speed limit
COOLDOWN : 5 seconds out of combat