Graves vs Master Yi

Position with no minion between you and your target: each New Destiny (passive) auto fires 4 bullets that can't pass through units.

Cast Smoke Screen (W) on their carries: inside the smoke, they're slowed and can't see anything outside it for 4 seconds.

Fire Collateral Damage (R) with your back to the danger: the shot knocks you backward, enough to reposition while dealing damage.

Cast Quickdraw (E) often during your clear: it reloads a shell, gives armor and magic resist, and each bullet that hits lowers its cooldown.

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.