Fiora vs Warwick

Position to hit the Duelist's Dance (passive) Vital: each Vital you hit heals you and gives you move speed.

Cast Lunge (Q) on the Vital's side: the strike prioritizes Vitals, and hitting an enemy lowers its cooldown.

Save Riposte (W) for enemy CC: it parries damage and effects for a moment, and if it parries an immobilizing effect, your stab stuns the first champion hit.

Hit the four Grand Challenge (R) Vitals by circling your target: if you hit them all in time, or they die after the first, you heal nearby allies.

Keep your health above 50%: below that, Blood Hunt (W) gives him speed toward you and attack speed, three times more below 25%.

When he drops below 50% health, finish him fast, with CC if you have any: Eternal Hunger (passive) then heals him with each auto, three times more below 25%.

If you have a dash, don't count on it to escape his held bite: Jaws of the Beast (Q) makes him follow all your movement, then leap behind you.

In teamfights, stay behind your tankiest allies: Infinite Duress (R) suppresses the first champion hit, and its range grows with his move speed.

If you have Grievous Wounds, apply it to him: his autos heal him at low health, and Infinite Duress (R) heals him for all the damage it deals.