Swap W and E for Corki and Tristana (and Some Others) to Match Ability Button Trends
http://na.leagueoflegends.com/en/news/community/q/ask-riot-runes-splash-art-and-buttons
Second, some types of abilities have trended into certain slots, and we try to follow those trends. When working on Kled, for instance, we were prototyping an early version of Jousting, his dash ability. We looked at similar melee fighter champions like Riven and Yasuo, saw that their dash abilities were in the E slot, and followed suit with Kled’s dash. Similarly, his purely passive attack modifier, Violent Tendencies, has similarities to abilities like Vi’s Denting Blows and Vayne’s Silver Bolts, which both live in the W slot.
Can we swap 
's Valkyrie (W) with Gattling Gun (E) ?
And 
's Rocket Jump (W) with Explosive Charge (E) ?
I think of E as Escape and and are kind of the exception among Marksmen with their ability placement. Also Tristana's Explosive Charge is kind of a passive attack modifier...
Maybe even 
's Blood Rush (W) with Stand Aside (E) ?
And 
's Move Quick (W) with Toxic Shot (E) ? Toxic Shot is a passive attack modifier and Move Quick is kind of a dash? I don't know.
As an aside, I think of 
's Spell Shield (E) as an Escape, so it fits the trend. 
also has Black Shield on E. However 
has a spell shield (Shroud of Darkness) on W, which does not seem to follow the spell shield / escape trend.... Granted 's Unspeakable Horror (E) can be used for escaping....
Also maybe swap 
's Riposte (W) with Bladework (E) since it's almost like a spell shield? Also having Riposte on E would match 
having Condemn on E or 
's Equilibrium Strike (E), which seem similar.... I'm not sure.
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