Fiora vs Cho'Gath

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 moving against him: Rupture (Q) strikes an area on the ground, and an enemy standing still takes a knock-up, damage and a slow.

Punish him when he goes for last hits: Carnivore (passive) restores health and mana for each unit he kills, and he lasts a long time in lane if you let him farm.

If you have range, keep your distance: his kit has no dash, only the slows from Rupture (Q) and Vorpal Spikes (E).

Don't stay in melee range at low health when Feast (R) is up: its true damage ignores your resistances, even if you're a tank.