Now, Gangplank is a champion I've been wanting to play for a little while. He's a pirate, which is something I'm quite the fan of if I'm honest. The problem was, until recently, he was quite an expensive champion.
Now, most LoL champions can be dull, but Gangplank is one of the fun ones. He has the abilities "pirate", which does nothing and "scurvy" which means... well... he has scurvy, which takes us neatly to his abilities.
Gangplank has 4 main abilities- parrrley, which shoots a target for a set amount of damage and has quite a quick cooldown; remove scurvy, where Gangplank eats an orange and gains health, as well as clearing any crowd control effects; raise morale, which increases nearby allied champions' attack and movement speed and his ultimate, cannon barrage, which shoots a barrage of cannons for a set amount of time anywhere on the map.
Gangplank also has a passive, grog-soaked blade, which means his basic attacks and parrrley apply poison!
Though people tend to use Gangplank as a jungler, my preference is to build him for attack damage. This essentially means you take the basic boots and three health potions which are the only items you have until you can afford a B.F Sword. Once you have a B.F. Sword, you can then buy either Mercury's Treads or Ionian boots of Lucidity. You do want to upgrade the B.F. Sword into Infinity edge pretty sharpish. If you play a long enough game, I'd suggest the Trinity Force as a good item to build along with maybe the Hextech Gunblade if you feel the need for a bit more AP.
I know I say this a lot, but I really enjoyed playing Gangplank. His ultimate move is over powered and he's generally just a good champion all round... But don't try to take on Teemo with him.