This guide is primarily meant for playing Kog in a duo lane bottom with support in mid elo (1200-1800) ranked games.

Kog is best in the bottom lane with support because he is one of the most farm dependent heroes in the game and has a solo laning game that is on the weak side. In a solo lane he is vulnerable to ganks as he has no escape moves and there are a number of good harassing heroes that can stop him from getting his proper quota of creep last hits. Putting him with a good healing support ensures his farming and protects him from ganks, setting him up for mid/late game where he dominates.

Kog received a big buff at the beginning of July 2011 which has been little talked about: Bio Arcane Barrage went from 6s duration 15s CD to 10s duration 17s CD. This means that instead of having W on 40% of the time, it can now be on almost 60% without any cooldown reduction, a 50% increase. This makes builds centered around W much more viable, especially combined with some other small buffs he's received this summer.

Kog's damage with this item build is split between magic and physical which means you should not be your team's only AD hero. Kog can fill this role with some items changes, but he will still do good amounts of magic damage. See Item section for more information.

Attack speed marks/quints are optimal, but you can get away without them (I run armor pen marks and health quints if my Kog rune page isn't set up). I like Armor/MR seals/glyphs for the big boost to survival and sustainability in lane.

I favor Flash+Ghost because good positioning is absolutely the key to playing Kog and these spells give you that. You are often the main target of your opponents but have no natural escape mechanisms. These spells also give you excellent chase down ability and allow you to quickly re-enter a fight if you were forced to dodge out to avoid focus.

The only time I would ever see something else being justified is getting Exhaust if they have assassin type heroes like Noct/Akali who are difficult to kite and will consistently focus you. But even still I think relying on your team for help and getting ghost/flash might be best in these scenarios.

W is obviously your bread and butter and needs to be maxed first.

I prefer E over Q for a few reasons. The biggest ones are the fact that Q has less range than your auto attack making it sometimes hard to use (you should be DPSing from max range always outside of chasing situations) and the fact that the slow increases from 28% to 60% which is a huge difference considering it lasts 4 seconds and covers a big area. Having better AE damage doesn't hurt either.

Take 23/6/1 Masteries for the extra defense, improved ghost, and improved firepower. Start with a Doran's blade to give you HP, make your harass hit harder, and make last hitting a tad easier.

Focus on last hitting as your CS will go a long way in determining how well you dominate later. Still, don't forget that you can put up some good harass with W, especailly if your opponents are getting too agressive. You should save your mana for spamming W and not use your other skills unless you can get a kill or you need the slow off E.

Start with boots and 3HP potions. Take 21/8/1 Masteries with 3 in Strength of Spirit for improved HP regen. Get one or two Doran's Blades on your first trip back.

Play passively and use W to last hit unless you are in a duo lane with an agressive partner. In certain solo situations it can pay to get agressive with the W harass but you need to remember that your CS score is paramount and you are vulnerable to ganks.

You need them. Lots. If you are in solo que, you can not rely on support to always be there to heal or anyone to do the warding for you.

Health potions allow you to continue to last hit under harassment. This build has no health regen because HP pots are all you need until late game. Always better to have them stocked and not need them than to miss a whole wave+ because you have to go back and heal.

Warding is the only surefire way to protect yourself from ganks. With HP pots, range, and wards, you have no excuse for not having one of the top CS in any game you play. A farmed Worm is a happy worm.

Wards also help you get kills you wouldn't otherwise. You often need vision to take full advantage of your range. This is true the whole game.

There are a lot of good item options with Kog. Your W adds a huge amount of damage: At level 9 against a 1500 HP hero it is adding 90 magic damage a hit, or 150 against a 2500 hp hero. With such huge damage output built in, plus your huge range extender, attack speed is the most cost efficient damage stat to build for especially early on. I am going to talk about your options here.

Sword of The Divine (SOTD) - Gives a huge attack speed boost as well as some magic damage. I favor this item because the 30 armor pen active puts it over the edge and makes it the most cost efficient damage choice of the cheap attack speed items (see spreadsheet below).

Wit's End - Very legit option. Probably best choice against teams that deal 70%+ magic damage. Gives cost efficient damage and attack speed. Only downside is you are paying for the MR as well.

Malady - Another good option. I tend not to get it because it provides less damage output than SOTD, although it is close enough that it doesn't matter a lot. The added magic pen is nice but not very big and there are better stats than AP for you to focus on.

Madreds - Great item on Kog but somewhat overrated early/mid game. Before people get their HP pools up there are simply more cost effective damage items. The high cost is also a detriment, gimping you (relatively) before you finish it. Still a decent choice for a second or third damage item.

Trinity - I recommend this item as your second buy most games before Madreds for one major reason: Utility. The slow is extremely useful, making you a chase down god. The extra damage on casting a spell is a huge dps boost. The movespeed is very useful for kiting and chasing. You can use every single thing it gives you, and each component is useful while you are building it. Phage should usually be obtained first followed by sheen.

More on Madreds vs Trinity - If you are having no problem auto attacking to your heart's content, just get Madreds. However, usually I find that you have to be extremely careful with your positioning with Kog. He is almost always public enemy #1 and hence you have to do a lot of kiting/maneuvering/avoiding to prevent getting blown up. If you don't have to do this, the fight is likely won no matter what items you have. Thus a typical close fight will go something like get position -> short attack -> re-position/kite -> short attack -> re-position -> chasing attack. Trinity is perfect for this style of play making chases, quick attacks, and re-positioning all easier and more effective.

Infinity Edge After you get SOTD and Trinity, I would recomend this item as your next damage item. See spreadsheet for reasoning.

More on other items - It's usually best to get either Banshee or GA after you complete 2 or 3 DPS items, depending on how well you are avoiding focus and how much magic damage the other team has. If I had to give a one size fits all recommendation, it would be to get Banshees after completing SOTD and Trinity. Frozen Hammer is alright but I find that getting that much health with no MR is not smart and Trinity is practically as good for chase downs (while providing other huge benefits). I don't advocate Phantom Dancer because the crit chance isn't very effective with so much damage coming from on hit effects until late game, when Trinity/IE/SOTD is just as effective.

More on AD Builds - Pure AD builds (IE/BC/PD) can definitely work well but I find them slightly inferior to this approach in most games unless your team needs some physical damage for balance (see spreadsheet). If you are going an AD build, you should definitely get SOTD first still. If the enemy team is stacking MR and not armor, get IE after trinity instead of Madreds.

See this spreadsheet for some build damage comparisons: https://spreadsheets.google.com/spreadsheet/ccc?key=0AnXagflZXpvzdEI2VDhzWG1abXFhQmZ6eEpwMWw1Z1E&hl=en_US#gid=0

Kog's biggest advantage is his range. No other AD carry can provide Kog's sustained DPS at such distance. Good positioning means staying at max attack range and constantly scanning for champions trying to initiate on you. In team fights while your W is on cooldown, play with extreme caution.

While you should always target soft targets whenever possible, your high DPS against most high health heroes allows to punish an out of position tank ruthlessly.

Positioning is the single most important skill with Kog. This build requires you to be pretty squishy, but your range, two slows, and two summoners should be all you need to survive in team fights. Be the master of the hit and run, and always be quick to re-enter battles.

Follow this advice and you shouldn't have a problem vomiting to victory!