I've only tried one game, I need to give it more of a shot. But against teams with 4/5 squishy champs, I think it could work.

My idea right now is Hail of Blades Sudden Impact

Item 1: Blade of the Ruined King or Kraken Slayer (using BorK until KS turns to Physical instead of Magic)

Item 2: Youmuu's Ghostblade (the active gives you basically a second ultimate. Hail of Blades comes up often enough that you don't need the AS from ult, so you can use this whenever Ultimate is on CD and alternate between the two as your engage tool)

Buy Beserkers before or after Item 2

Item 3: this is where I get lost a bit, and it definitely needs workshopping. I've only played one game so far. But the Item I'm using, and the item that gave me the idea for this build, is Prowlers Claw. Now that it gives bonus dmg after exiting Q, I think it's a really nice burst tool for this playstyle, at least in theory.

This leads to a much more in and out playstyle, looking to blow up the highest priority target and run away, repositioning until you have another target to jump on. Also, for whatever reason (maybe lethality), you do really decent damage to turrets with this build.

I've only played 1 game with it so I will be spamming this build or a similar one in my games whenever I'm not against all tanks. Curious what the thoughts are, and why could this be bad?

Edit: Youmuus is getting its Lethality nerfed in the next patch. Lowered AH, lowered Lethality, and slower stacks for the Passive. With that said, I think it still may be worth trying Bork/Kraken into Youmuus into Bork/Kraken on next patch.