I'm BladedOctopus, and this is my first and currently only guide here on Mobafire. Corki is a very powerful carry who is highly respected by the more competitive community but sadly underplayed by casual players. While I myself am no pro player, I do consider myself to be a cut above average.

FILLER

This guide is aimed at giving newer players an idea of how to play as Corki. He carries hard, is an asset to his team, and most importantly, He is very fun to play.

FILLER

Things that I am planning to add at a later date...

• Early, mid, and late game gameplay tips and guidelines
  
• More pictures

• MAY 2012: Item selection in builds is completely redone, new builds created, Items section completely redone, Added personal experience to summoner spells section; specifically to Surge and Teleport, Small grammatical changes to each section
  
• JUNE 2012: Small grammatical changes to each section.
  
• JULY 2012: I changed the whole guide because I wanted practice with the coding.
  

Corki has a good mix between magical, physical and true damage, making him harder to counter than someone like Sivir who deals all physical damage.

Post 6, Corki can dominate his lane with Missile Barrage, effectively zoning out opponents and getting CS with ease. BUT Since he will be pushing pretty hard with his ult it leaves his lane open for ganks, if you're not prepared. More experienced players shouldn't have much a problem with this.

Combined with a high attack damage, Corki's passive, Hextech Shrapnel Shells, allows him to be a tiny terror later in the game. BUT You can only have beast mode 'on' at late game if you get farmed and fed in the early game. Like all other ADC's in the game, Corki loves him a good farm, because he NEEDS items.

Hextech Shrapnel Shells & Gatling Gun Gives Corki and his team a chance to focus down a single target very quickly. BUT Corki has low AA(auto attack) range compared to other carries. His 550 range is longer than Twisted Fate, Twitch, and Sivir, but he is easily outmatched by Caitlyn, Ashe, and Tristana. He needs to get dangerously close to the fighting, so you need to assess every situation to decide when to jump in.

Every single ability in Corki's kit has an AoE. This allows for easier harass and very strong lane pushing. There isn't really a con to that. BUT His spells have high mana costs, and he frequently goes oom without blue buff. It's extremely inconvenient to run out of mana in the middle of a big team fight. His heavy also AoE makes him play best with teammates that also have AoE.

I've never had a boring game as Corki. He is just a blast to play and I never get tired of him. He has a cool character model, his voice and sounds aren't lame, and he has pretty nice skins. BUT He can't really just be picked up and played like a master at the start. He takes a lot of practice to do well and isn't a good choice if you're just starting to learn ADC's in general. Also, I don't get his jokes.

greater mark of desolation Armor pen is amazing for Corki since it lets his passive do it's magic. Getting these lets you kite and harass like a boss throughout the match.

Armor runes to make you more resistant to harass in the laning phase. If you can take more punishment you can stick around longer and keep your farm up.

Since AP champs scale off of levels, and are usually focused on bursting down the highest priority target(usually the AD carry), you need MR per level runes so that your MR scales when their abilities do.

greater quintessence of desolation Having as much armor pen as possible helps you drop targets even faster. These can be swapped out for flat damage(for making you more powerful early game), damage per level(for stomping late game), or critical chance(if you're feeling frisky) quints.

OFFENSE
21 points in offense to make Corki carry harder. Since we're rushing Bloodthirster we don't need the 3 points in Vampirism . I take every damage increasing mastery that I can and get a point in Summoner's Wrath to get the bonuses for Exhaust and Ignite.

DEFENSE
9 points in defense to be a bit more durable for early game. Durability is actually a pretty sucky mastery, but we get points in it anyways so that we can have Veteran's Scars . 9 points in defense lets you stick around in lane for longer.

UTILITY
I don't put points in this tree, but I guess you could try to to put points into Expanded Mind and Meditation to help solve mana issues early game, but I don't think the mana regen will be enough to feed Corki's hunger for mana.

This is what makes Corki a real terror during fights, and this passive is also the reason Phantom Dancer isn't a core part of this build. It makes it more difficult to build resistances against him, since he just punches right through them. This also applies to critical hits.

This is what gives you your single target burst. We max it first so that you can be more effective early-earlymid game during fights, and because early-earlymid game is when it is most effective. It reveals the area hit for a short time, so try to make use of this before big fights break out.

This ability, paired with flash is what makes Corki incredibly hard to gank. Since it functions exactly like flash, you can use it to jump walls or close ditance if you need to. You should never valkyrie in to start a fight, that's your tanks job. Save valkyrie to clean up fleeing targets, and save flash for running away just in case.

This is Corki's signature ability, it lets your team instantly wreck the face of the person you're focusing. It turns armor into swiss cheese, so tanks building armor to counter you will be sadly disappointed.(I'm not implying that you should focus the tank) Make sure to let your team know who you're target is so that they drop as fast a possible. Keep in mind that the armor reduction is only applied while the target is under continuous fire.

Post 6, Corki's aggressiveness in lane shoots through the roof because of his ultimate. The best part about this ability is that you can spam it. And because it's spammable, spam it. Use it to check bushes, zone out opponents, proc the Trinity Force passive, and push your minion wave(push it real good). It's a very straightforward ability. It works off of an ammo system like Teemo's Noxious Trap, so try not to run dry in the middle of a team fight.

Boots is a good starting item, it lets you juke skill shots, and helps prevent early game ganks. Health Potions are an obvious choice, they get your health back up when it gets low, and your support can't be expected to pick up all of your slack. RECOMMENDED when you play with a support that has healing ability.

FILLER

Doran's Blade is my preferred starting item, since I usually end up buying one anyway. It boosts your starting HP, and AD. The AD you have by starting with a Doran's Blade helps you last hit minions, and with Hextech Shrapnel Shells, lets you effectively harass your opponent with only your auto attacks. RECOMMENDED start with a sustained lane partner

If you are doing well in lane, you should easily be able to get the money for these realtively cheap items. Double doran's blades+sheen give you all the damage you need this early, and a vamp scepter gives you decent sustain.

If your team is winning the game, your highest priority item should be Trinity Force, then begin building into Bloodthirster with a BF sword. However, if your team is losing, finish your Bloodthirster first, then build Phage into Trinity Force.

This is an example of an build you could have at late game. It maximizes damage output while giving some decent survivability through Banshee's Veil.
The 80 AD boost that this item gives is ridiculous. With this item alone, about 1 in every 4 attacks will be a critical strike. Add on the passive from Hextech Shrapnel Shells and you're dealing scary amounts of damage.

The Maw of Malmortius gives a 55 AD boost, which is pretty good. The magic resist you get is pretty decent, and the magic blocker you have every 60 seconds can be a real life saver if you get focused down by enemy casters. It also gives you more damage per missing health. An item made for Olaf, but it can work well on Corki too.

Even though Gatling Gun shreds armor like nobody's business, its effect is only applied when the target is under constant fire. So, Black Cleaver is still an excellent item for its AS and AD, and its passive for when Gatling Gun is on cooldown. This item is better if the enemy team doesn't have much armor.

This item doesn't give the damage or attack speed that Black Cleaver does. However, late game, the enemy tank may be stacking armor to counter your high AD. 40% armor penetration is a lot if the enemy tank has 200 armor. If a situation like this happens, I'll switch Black Cleaver for this item.

the attack speed boost on this item is huge, and the increased crit chance and move speed are nice too. Since you need to make the most out of his passive through high AD, this item shouldn't take priority over something like Infinity Edge.

The %age health based magic damage is a huge threat to any champion stacking health items. The armor is also nice for more survivability, and the AD and AS boosts are almost on par with those of Black Cleaver.

AD, critical chance, cooldown reduction, and armor penetration. Also, an active that lets you chase and kill or escape and live. All good things to have. If you find yourself needing to deal more damage but dont have the money for a more expensive item, this is a solid choice.

This item should not be bought as a late game item. It is only effective when bought early-mid game to help solve mana problems. Its effectiveness drops off very quickly, since mana problems are for the most part solved by blue buff. If purchased, should be sold later on to make room for a different item. A good item for players who are not yet experienced enough to know how to manage their ability use.

On-hit, you get extra magic resist and deal magic damage. Mix this with boosted attack speed and you get 30+20 extra magic resist in just a couple seconds. Best for on-hit champs like Kayle, but it could work on Corki.

Everyone knows the Guardian Angel. A free life every 5 minutes is always nice, but it usually only works the first time when enemies don't yet know that you have the item. After that, as soon as you die 2 or 3 enemy champions will stick around and try to get the kill. The armor and MR are the only real bonuses. It's very cost effective for what it gives.

I personally haven't tried this item, but its active seems almost too good to pass up. It functions exactly like Cleanse, without taking up a spell slot. It could be used to shrug off a Warwick when he hits you with Infinite Duress, or to escape from a Skarner when he catches you with Impale.

• Corki is different from other carries, in that he has to use his abilities constantly to max his damage output, unlike an auto attacker like Ashe. He is basically a more powerful version of Ezreal, imo. If you're not using your abilities constantly during fights you're doing it wrong.
  
• Since Valkyrie is your escape tool, don't use it offensively, and make sure you always save enough mana to use it just in case. In the laning phase, play passive when it's on CD, and put the pressure on when its back up. If you really need to make some distance, W+ Flash creates a huge gap between you and your chasers.
  
• Learn how to last hit. Corki is so easy to farm with, and he needs the farm to be effective throughout the match. I don't want to go over the specifics, so you can look up a guide on it somewhere else.
  
• Don't be afraid to use Phosphorus Bomb to pick up some 2 minion kills if you would only be able to get 1 with your auto attack. Just make sure you save mana for Valkyrie.

Can't think of anything else.

If you got this far, thanks a lot! This is my first guide here on MobaFire, and I know it's kinda long. Blocky text and all. If this guide helped you play this great champion, leave a comment, and vote me up.

Thanks for reading my guide, and happy playing!