Gangplank vs Sion

Build a chain with Powder Keg (E): detonate the keg farthest from your opponent, and each keg whose area touches the previous one explodes too, all the way to them.

Last-hit minions and pop kegs with Parrrley (Q): a kill with the shot gives bonus gold, and so does a kill from a keg it sets off.

Save Remove Scurvy (W) for a key CC rather than for healing: it cleanses all CC on you, on a 22 to 14 second cooldown.

Cast Cannon Barrage (R) anywhere on the map to help a fight or cover an objective: each wave of cannonballs slows and damages in the area.

Leave the area while he charges Decimating Smash (Q): past 1 second of charge, the hit applies a knock-up and a stun, for up to 2.25 seconds.

Break the Soul Furnace (W) shield before he detonates it: he can only trigger it if the shield still holds.

Step to the side of Unstoppable Onslaught (R): he turns poorly once it's launched, and his charge stops on the first champion hit.

Back off as soon as he dies: during Glory in Death (passive), his autos are much faster and deal damage based on your max health, but his health drains fast.