Quinn vs Cho'Gath

Cast Vault (E) on the melee champion charging you: you leap back after the hit, and your target is slowed and marked by Harrier (passive).

Auto every target marked by Harrier (passive): your first auto on them deals bonus damage, and Heightened Senses (W) then gives you speed.

Against a melee champion, trade from range: Blinding Assault (Q) marks them with Harrier and reduces their vision before your empowered auto.

Roam with Behind Enemy Lines (R): after a 2-second channel, you gain a lot of speed, and an auto or a spell ends the flight with an area attack.

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.