Hi guys, be sure to read the notes on the items.

Use your Q to farm. The bonus gold fromand your is what will set you apart from your laning partner.

Poking with your Q can cost a lot of mana if done in excess so I would recommend waiting till around level 4 when you have the bonus damage from your E and a higher crit chance from your to start poking with it.

Kiting around the back of your minion waves and last hitting with your Q and occasionally poking your enemy is key.

Mid game starts for GP when he has his 3 core items:
Static shiv, Infinity Edge and Ninja Tabi.

You have two main goals during mid game:
1. Outfarm every single person in the match and stack gold like a son*****.
2. Roam the field with your super duper movement speed and gank the **** out of people with the slow from your passive and your unholy crit damage.

Pretty basic stuff.

GP's ult is odd. It's a global circle of random cannonballs.
Anyone in the circle upon casting will be slowed and continue to be slowed if they remain in the circle. The cannonballs don't do a whole lot of damage but, if you drop it on bot lane when they are in the middle of a fight it can do just enough to help them get the kill or at least scare the opponents.

Also another appropriate time to use your ult is when you are across the map with your team and there is a huge creep wave mashing on one of your towers. You will often clear the entire creep wave which will give you tons of gold and save your tower.

I will ult during every team fight if I can, the potential damage and the slow makes for a pretty unfair advantage in a team fight.

Spirit visage is my personal favorite. It makes your W more than just a cleanse; it can actually heal you. The CDR is also just too nice. And since the recent buff it also gives you 400 health with is wonderful for GP who is notoriously squishy. And of course the gnarly MR this item gives makes it very viable for GP.

Warmogs is also pretty great for the squishy GP. I only get this item if I'm just raping everyone so they all start to focus me. It also stacks well with...

Atma's impaler. The passive on this item stacks well with, obviously, any health item. The armor and crit chance are also welcome on GP.

Frozen mallet is also viable, it will give you health and damage which will help add to your crit damage, obviously. The slow from this item isn't the reason why you would buy it due to the slow you already get from GP's passive. It's mostly just a way to get tankier and not feel bad because you are using an item slot that could add more damage.

Trinity Force, I almost never buy this item. The spell blade is the main reason people get this (I would assume). The health it adds isn't that great, GP doesn't really have mad mana problems, the on hit slow is already taken care of by his passive and it only gives 10% crit chance. The only reason why I don't build this very often is because spell blade can't crit. It just adds a certain amount of damage to your Q which isn't really necessary. I would rather build something like a blood thirster over this item because it will stack with your crits. This is just my personal opinion, spell blade seems to just be a play style difference. (If spell blade could crit this item would be OP as ****). Oh, also the added AP from sheen is only 30 which doesn't really help the damage from his ult and the heal from his W very much. It still is a reason to buy it though. If you are trying to make his W heal better, I would recommend the spirit visage.

Last whisper is viable on any AD champion but, is quite useful on GP. When late game comes around and I find that my Q isn't melting people like it was 5 minutes ago due to builds being finished, I will sell something like atma's impaler and replace it with last whisper so I can break through their armor better. I imagine the black cleaver would also work however, you have to hit the enemy multiple times to melt their armor which your Q doesn't really do. That's why I prefer the last whisper, it's better for kiting and instant gratification.

Randuin's Omen is viable for your health item if your team is getting shat on by the enemy ADC. The active slow is also nice for chasing but, not the reason to buy this item.

Thanks for reading my guide, it's my first guide on this site so I couldn't really figure out how to get the pictures and stuff to work...but, yeah. Please don't down vote if you disagree with my build, leave a comment with your opinion of why it sucks. I've found this build to work wonderfully and hope people try it, I wouldn't want them to never see it just because it got down voted by some random hater.

Have fun guys!