Hey I'm here with a build on Corki... And here is how to play an awesome Corki.


Lets get to it.

Pros:
Epic Escaping, and some nice Juking
Underestimated Damage
Amazing long range poking
Easy farming, and good late game farming
Most useful AD Passive in the game (According to me.)
Good AoE if you build him for it
Epic Mustache
You can ride a seal. A. Seal.

Cons:
Really Squishy
Easily out harassed early on due to his short range
Often Focused if doing well.
Bad Farming = Awful game
Needs a competent laning partner.

Pros + Cons are pretty even, But I'd give Corki about a 7 on the Difficulty scale, because his short range and positioning in fights need some practice to get down.

Reds
Greater Mark of Desolation Flat Armor Pen which goes into good late damage.


Yellows
Greater Seal of Armor I find these to be Alright for seals, but they're not excellent
Greater Seal of Scaling Mana Regeneration I love these, they give you that Mana Regeneration you need to sustain yourself in the mid-late game, but there are other seals if you're good with your mana (Which I'm not :P)
Greater Seal of Attack Speed Same as the Reds, but these would be a good choice for you if you are fine on your Mana
Greater Seal of Attack Damage/ Greater Seal of Scaling Attack Damage These are like the Alacrity seals, if you think you'll be fine without the Mana Regen, the difference is these will scale well for you into the late game, giving you a better attack damage setup, because you will have alot of Attack Speed already.

Blues
Alright, I'm going to be honest with you, AD carry Blues send me into a tailspin (Pun Intended, Cuz it's Corki... and he's a pilot... Haha.... Ha...) Anyways:
Greater Glyph of Scaling Magic Resist These are my favorites, because they give Magic Resist, and most enemy Champions have some Magic damage.
Greater Glyph of Scaling Mana Regeneration It's a pretty nice Glyph if you have minor Mana problems and don't think you'll need the Magic Resist.
In all honesty, most of the useful AD Runes are in Marks and Seals, so the Glyphs can be used for anything you want, those 2 are just what I find useful for Corki.

Purples
Greater Quintessence of Desolation Pretty Standard AD Quintessence, paired with the Desolation Reds, and ANY Armor Pen item, plus your Gatling gun, tanks will Run with their Tail/Poison/Rockness/Sword/Shield/Lance Between their Legs.
Greater Quintessence of Scaling Attack Damage These give you an extra 13.5 AD, which is nothing to sneeze at.
Greater Quintessence of Attack Speed Once again, these are nice for the Attack speed,

(On a final don't get Quints in Might if you have them in Seals/Glyphs, and don't go for more then 1 Alacrity set. (I.E. Getting Alacrity Marks and Quints would be a waste)

(Note: Recommended spells for Corki)

I love this Spell on Corki, it Drops Ignite, Exhaust, Taunts, and Stuns. Plus it's on a relatively Low Cooldown (3 1/2 Minutes, roughly once every team fight in the late game, which will be where it counts)

Flash, Oh Flash. How I love you, Flash, Pair this with Valkyrie You will be Getting out of there before they even know you left.

Another good one, if you don't like to take Cleanse, it will let you 1v1 ALOT of enemies.

Same as Exhaust pretty much, a good one for skirmishes and getting the extra early game damage you need.

It's a good replacement for Flash, if you want to GTFO then you can Valkyrie, which will put you out of CC range and you can run like a Bawss.
The Bad

(Note: These are Viable but not recommended)

Ehhh. It's alright, but the Attack Speed boost will be Not needed in the major team fights, and Exhaust or Ignite will work better 1v1.

If it gets to the point you need to use Heal, you're gonna already be dead anyways, so don't get in that Situation!

Again It's alright, but when you get to the later game where you aren't mana Hungry, you'll be down a Summoner Spell, but yet in a early game at mid its very useful.

I personally don't like this one on Corki, just because you're main goal as AD carry in early-mid game is to Farm and not die, and you shouldn't be Teleporting to another lane as the AD carry.
The Ugly

(Note: Just awful spells. Don't use these for Corki, please.)

Really. Just don't die, which is kind of your job, and you'll be fine.

Mainly just for the Supporter people, not at all useful for Corki.

Stop Trolling me and go pick a better spell, Jungle Corki is NOT Viable, unless it's like, some crazy new thing that I haven't heard of.

I'm not really gonna go TO In depth on the Masteries, because with the new Masteries, you will probably want to experiment with your own setup.

Brute Force Standard for AD Carries going Offensive
Butcher I know that this is used mainly for Jungling, but It helps me take down the last hits for the first 3 or 4 levels, when 4 damage can make the difference.
Alacrity Again, pretty Standard for AD
Weapon Expertise If you're gonna get Alacrity...
Deadliness Why not Havoc ? Because I love Crit with Corki, however, if you're gonna build into a more "pew pew shred them" damage style, then definately go with Havoc
Lethality If you go with the Shred them Sustained Corki, not the Burst Crit path, then take the point you have left from this and throw it into Vampirism, Otherwise, this is great for Crits on Corki.
Vampirism combined with the Doran's Blade will let you take 5-6% Lifesteal to start the game off.
Sunder Armor Penetration! 1/2 off!
Executioner If you put 20 points into the Offense tree and then skip this...
Now that you have the Offense tree all set, you can do a few things.
Fill Resistance And Hardiness then put the last 3 in Vigor
Put 2 points into Resistance And Hardiness then go into Durability and Veteran's Scars
Put the last 9 points into the Offensive tree, however you want.
Go into Runic Affinity If you like to take Jungle Buffs alot




Anything you want to do with Masteries will probably work well, (Unless you go all AP as AD Corki, but, Y'know... Common Sense and whatnot.) Play around with it, have some fun.

Okay, so, Maxing Gattling gun first will allow you to win a fight 1v1 and send the enemy packing, Valkyrie is maxed last because we only use it for escapes/chasing, seeing as how we're AD, we also don't focus on Phosphorus because this build is geared for end game Kills, early game awesomeness. You will have a high Poke with your Phosphorus, seeing that you land it, and your E will still help you out some, just don't get in a sustained 1v1 fight, get in, do your poke, get out.

I will be going over item choices, a core build and some extra items.
You're going to want to start with either Doran's Shield if you won't be laning with someone who can heal you, or Doran's Blade If you will be with a healer.
On your 1st B get your Boots and either a Null-Magic Mantle or a Cloth Armor if you're being harassed by AD or AP, otherwise go straight for Berserker's Greaves if you're dominating. At this point, you're gonna rush your Bloodthirster To give you your sustain, now, assess the situation, if you are doing very well, no fear that anyone will best you and you want to get even more aggressive, go right on into your Trinity Force However, if you are not doing so well in your survivability you might want to go into a Guardian Angel if you need armor and MR and want the second chance sort of thing, Frozen Heart If the enemy team is super AD heavy, or Banshee's Veil for an AP heavy team. If you rushed your Trinity Force go into your Defensive item, according to the enemy team's composition. If you went into your defensive item then grab your Trinity Force
Now then, The last 2 items, have many different ways of being used, so I'll list a few things to counter situations.

The enemy team has gone all Tanky high Armor! Help! Easy to counter, you get yourself a Phantom Dancer And a Madred's Bloodrazor Those tanks will not know what hit them.
The enemy team is now starting to Focus me down!
You're gonna want to grab some defensive stuff, again go according to the enemy team, AP heavy, AD heavy, and so on, but a good item for Defense on Corki would be, In my opinion, a Frozen Mallet and a Last Whisper The Last Whisper will put your Armor Pen over the edge, while the Frozen Mallet + Other Defensive item (I highly recommend the Guardian Angel if you're being Focused hard, because in the heat of the moment, you see a corki at 1 HP you're gonan be spam clicking him, at least at lower levels, and that will give your team some time to kill them.) Will keep you kicking.
My team is doing well at protecting me, but I don't know what I should build. At this point, you can experiment, I like the Phantom Dancer + Infinity Edge build myself, but you can also go into some other items, like, Black Cleaver + Last Whisper For Super Armor Pen
Or Black Cleaver + Madred's Bloodrazor Just play around with the last few items, have some fun with it, you gotta have fun with the game. :P
Something I have to Add in before I start the Rennovations on this section:
Quicksilver Sash If you want to swap out one of your 2 end game choices for this bad boy, which is basically Cleanse on a shorter Cooldown and some Magic Resist, so that you can go into something like Exhaust or Ignite for yourself, if you prefer this to Cleanse then, More power to you.

Alright, I'm going to keep this one Short and Simple:

Early Game

You want to see who you're laning with and grab the associated Doran's item, You'll want to work on your Farm for your first 6 or so levels, Then start poking with your Ult, try to stay in lane as much as you can, and don't be stupid, if you're being denied farm, let it happen, you can farm in the late game as long as you don't feed in the early game.

Mid Game

At this point you're gonna want to be staying with your team, wherever you're starting to be, continue to farm if there's nothing happening, and ask your jungler if you can take red time to time, it works well with Corki for chasing.

Late Game

Team fights will be breaking out left and right, which is where you want to be careful, DO NOT charge straight into a team fight, count out in your head, One Mississippi, Two Mississippi... Then jump into the fight, get close enough to be hitting them with Gattling gun, but be able to Valkyrie out if things get bad. Phosphorus bomb will help the fight, and keep on the Missile Barrages.

REALLY Late game

At this point it's 60:00 into the game and you're at full build (I hope...) What you can do here, is swap your Beserker's Greaves For another Phantom Dancer, if you want to, but I'd grab the Mercury Treads if you're getting CCed a lot.