Gangplank turned out to be quite a good counter to nasus
And he's actually recommendable to low elos and such unlike teemo(satan,there I said It) who requires somewhat decent kiting mechanics.
His harass pattern Is simple:Put a barrel near low creeps or wait for him with your passive up,or both! It's a bit predictable,but so Is Nasus's laning phase.
Free stacks on barrels?nope.
armor?speak to the barrel.
Wither/ganked because wards are usele...I mean the enemy took you for Dyrus?Not a problem for a man packed with Vitamin C goodies.
Pain In the pirate booty splitpusher?global click wave clear says no.
I think he's a nice trump card to have,kind of like Malzahar vs Cho.