Miss Fortune's W + Runaan's is the key of this build.
I would get Statikk Shiv instead of Mercurial Scimitar, because it procs faster with Runaan's and crits too and gives crit chance. I would get Blade of the Ruined King instead of Frozen Mallet, but Frozen Mallet is good too. BOTRK procs on all 3 targets too. These builds are very good with Jinx, Kayle and Kalista too. Runaan's+BOTRK could work on Gnar too. The problem however is that he would go into Mega Gnar mode very fast. I haven't tried it yet though.

great

great

great

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This guide was straight and to the point, unlike quite a few other guides here, and is deserving of a +1 because of it's well-thought out item choices, although most of the guide looks like a wall of white text, this is easily fixed with columns, lists, dividers, and other such nonsense.

+1

Awesome build