Master Yi vs Gragas

Cast Alpha Strike (Q) to dodge a spell or a burst: you're untargetable during the strike, and your autos lower its cooldown.

Cast Meditate (W) to tank a burst mid-teamfight: you take less damage, heal more at low health, and the time left on Highlander (R) is paused.

Activate Highlander (R) to chase: you gain move speed and attack speed, and slows no longer affect you.

Chain kills in teamfights: each takedown lowers the remaining cooldown of your basic spells, and extends Highlander (R) if it's active.

Stay behind your minions: Body Slam (E) stops on the first enemy it meets, minions included.

Get out of the Barrel Roll (Q) area right away: the longer the barrel sits on the ground, the more its explosion hurts and slows.

Step up when Body Slam (E) hits nobody: its cooldown isn't reduced and stays at 14 to 12 seconds.

Spread out from your allies: Explosive Cask (R) knocks every enemy away from the impact, which can split you up or send you toward his team.