Fiora weakness?
You buy health? No, max health true damage You buy armor? No, true damage Wait for her to go oom? Ridicolous mana costs, almost manaless Use crowd control abilities, such as stun, slows, suppressions, even some summoner spells? Lol get parried bro You try to duel her because you are Tryndamere, Jax or Irelia? Get your attack speed lowered mate. By fifty fucking percent, ah You try to blow her up? Nope, tank build
She punishes everything And look how retarded her kit looks. I mean she has more things than Lee Sin. Her passive deals max health true damage; but it also gives movement speed (a fucking ass huge boost, not a minor one) and actually heals her, lmao. Her Q is basically a tumble, but it even applies on-hit effects. She has invulnerability thanks to her parry; but not only, she can also stun, slows and can halve your attack speed. Doesn't that sound fun? Well, it gets better. Her E makes her next two basic attacks gain range; one of them slows and one of them crits. Her ult, well, do we need to comment? Riot Games :j
If you look at the global picture, the whole character of Fiora is retarded as fuck. Her kit is telling you: "What? Ok, we can go even in lane. You can beat me in lane. But you will never be stronger than me. And I'm going to rape your team by the time I complete my third item. And you are going to get punished for doing anything possible to stop me."
I know she's getting some fixes in next patch but I just wanted to analyze better her kit. Imagine a tanky melee Vayne that can't be kited or something.
Step it up

. Her passive kept me on edge, like an actual duel. It's glorious.
. Even before the change to his passive, I learned how to kill him as