Hi this is my Gangplank guide, it is based off playing 3s and 5s, both ranked and normals.

Pros:
-His passive is REALLY REALLY great early game.
-He has great dps, and burst.
-Tanky late game can take damage.
-Global ulti can save you or your team mates where ever.

Cons:
-really needs a kick early game to be reliable in mid game but amazing late game.
-hes op nuf said lol

Now first I rush Wriggle's lantern, "But you're not jungling?"....Well it's a very useful item, I think wriggle's Lantern is a must have for tanky dps such as Gp or Xin and etc.

Then I get Berserker Greaves, BUT you can get Mercury Treads if their team is CC heavy.

Then I get a Tri-Force, this is GPs main item. I mean parley, slow, auto attack with tri force proc, slow, kill for the win really op on GP.

Then I get last whisper for the extra armor pen and the kick.

NOW for the last items it really depends on the enemy team but most times I get warmogs and atmas just because he gets so tanky that hes just unkillable. But if your team lacks damage you can get IE, then a Phantom or Banshees. But once again Warmogs and Atmas is great on him, highly recommend it.

Farming:
You have to remember when you kill a minion with your parley you get extra gold and that is why I max parley first to get more of that extra gold. Its really helpful and op imo.

If you can parley last hit without auto attacking and if you do it well, you'll be at 100 minion kills in no time and can dominate lanes and gank with ease.

Oh yeah and always try to get top lane with GP.....and BUY wards.

Team fights:

Now in team fights, what gp is great at is taking down the carries, parley and tri force proc literally 3-5 hit a squishy carry, even faster if you have last whisper. But overall in teamfights try not to get too much involved, you just want to use your E then auto attack, parley then auto attack, w then auto attack. Use that Tri force proc well, it huuurts.

I hope you've found this build helpful, this guide really is not an indepth guide but is a guide on how to carry with GP early and late game very easily. Remember GP is really op atm and you need to take advantage of it.