Fiora is extremely over powered. She seems to be very cool down dependent so I added in a bit of reduction. Her ult, and ton of attack speed from her E make on hits amazing so I also comprised this build of that. I hope you guys enjoy the build, she's pretty squishy early game but pretty much all carries are, make sure you have a baby sitter.

Standard runes and masteries for a carry. I highly recommend the runes, if you'd like to switch the masteries to 21-9-0, that also works but I prefer the increased buff duration because you can get red easily on your own with the early Madred's.

This gives her heavy damage output like a carry should have. Her ultimate applies on hits which include life steal as well so I use a lot of life steal and On-Hit affects along with burst of speed.

A lot of people suggest Mercury Treads but I believe the Boots of Lucidity are necessary to keep you alive. Other than this, the only thing I would suggest changing to your liking is the Trinity to a Frozen Mallet if you need more tankieness.

Burst of Speed it's your prime damage source so I max it early. I take a point in lunge early as a utility/chasing skill. The starting point on your W starts you off with high passive damage and a block. You could max it first if you felt it was needed, but I would say to max Lunge last.

Exhaust and Ignite are extremely useful in 1 v 1 situations which as a duelist you will be in a bit. If you don't like these, Flash is always an all around useful spell to have. It's a very uncommon pick but Surge in conjunction with Burst of Speed can be a deadly combo.
Everyone has their own preference but those are the ones I highly recommend.

I'm looking into different routes but for now I will say, coming soon.