Gangplank vs Malzahar

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.

Get out of the Call of the Void (Q) zone quickly: its two portals fire after a short delay, and their projectiles silence you.

If you have CC, hit him first with a cheap attack, then wait a moment: Void Shift (passive) still ignores CC right after the first damage.

Stay away from minions hit by Malefic Visions (E): if they die, the visions jump to the nearest enemy, and his Voidlings follow them.

Take your trades before he hits level 6: after that, Nether Grasp (R) can lock you down from range while his team hits you.

When he casts Nether Grasp (R) on an ally, focus him: he channels in place, and any CC interrupts him and frees your ally.