Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Tank/Critplank! Gangplank is a solid character, that has a build in clense/heal. Which is great for staying in fights. He also get very "nukey" in latar game.
Pros and Cons
Without Scurvy has no real "escape" abilities
Easy to Harass
You should start off with Doran's Ring for the quick hp boost/mp regen. Your team will probably laugh at you for going "ap" GP. Laugh at them knowing that they will be begging for you to fight with them later on. After that pick a lane and start harassing with your parrley and pop off a few scurvies for those quick heals. Also take any opportunity to take any kills for the gold. Never stop fighting. Only go back to base for the quick heals and item purchases.
By this time you should pick up some boots and fighting and fighting with your team. Sometimes your gun needs reloading, so don't be forget to go in there and let the other team taste your grog-blade! As you progress pick up a frozen mallet, this should allow you to off-tank, and also get those damn runners with your parrley. Also use your ult whenever your team will engage the other team. That'll make things more fair.
Build your inf edge the dmg way, with pickaxe or bf sword, with crit cape last.
Now that things are set with your new and shiny inf edge you should be popping off those crits. With time you should be getting PD. Build PD the crit way with purchasing crit cape/brawler's glove 1st working your way to zeal then finally PD. By that time you should be headshotin everyone that even dares to step into your parrley range. Pick up some lifesteal/MORE CRIT!!. by this time it should be your team destroying everything, leaving the other team trembling/awe at your power. If it gets even pull farther into late game trade out your Daron's ring for BT. If it even goes father then that sell your boots and buy all 3 buff potions and rebuy your boots.