Gwen vs Cho'Gath

Land 4 autos before Snip Snip! (Q): each auto adds a snip, on top of the first and the last.

Land the center of Snip Snip! (Q): in the center, part of the damage becomes true damage and each snip applies A Thousand Cuts (passive).

Place Hallowed Mist (W) against poke and ranged CC: enemies outside the mist can't target you, except towers.

Cast all three Needlework (R) activations within 6 seconds: the first throws one needle, then three, then five, with growing damage.

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.