Viego vs Master Yi

Weave in an auto after each spell: thanks to Blade of the Ruined King (Q), your first attack on an enemy damaged by an ability strikes twice and heals you.

Charge Spectral Maw (W) when you have time: the longer the charge, the longer the first enemy hit stays stunned, but you're slowed in the meantime.

Cast Harrowed Path (E) on a wall near your target: inside the Mist, you're camouflaged and gain move speed and attack speed.

After a kill, hit the wraith to trigger Sovereign's Domination (passive): you restore health and take their basic spells and items, but not their ult.

Cast Heartbreaker (R) to finish: you leave the possessed body and strike the champion with the lowest health percentage, with damage based on their missing health.

Against Highlander (R), don't run alone: regroup with your team, because he gains speed and ignores slows.

If you have CC other than a slow, land it right after Alpha Strike (Q): during the strike, he's untargetable, and Highlander (R) ignores slows.

If you have CC, interrupt Meditate (W): he channels it to heal, more at low health, and to reduce the damage he takes.

Put pressure on his jungle early on: Master Yi is strongest once he has his items, and each stolen camp delays him.