Kog'Maw is a Kog'Mawcute(in my opinion) character that can be really deadly when made well. There are two ways that one can go with Kog, AP: shooting the living artillery like crazy and dealing 800 damage with rolling puke or AD: being sneaky and killing the opponents in the shadows and being a jerk that everyone wants to kill. This build is, as you can see in the title, the AD build.


THIS IS A BUILD I MADE PLAYING KOG'MAW AND IT IS CERTAINLY
NOT THE BEST, THERE COULD BE BETTER BUILDS, BUT I AM JUST SAYING THAT THIS
BUILD WORKS GREAT SO TRY IT.

As you can see in the masteries above, this build requires a mastery that will give a lot of damage. I could have selected some AP damage, but my thought is that when Kog is going AD, just pure AD is perfect. Hybrid Kog might seem good, but it is not that efficient as just pure AP or AD.
The reason why I chose the [Summoner's Insight] of the Utility is because for this Kog, teleport and flash works really good. Flash is obviously when one needs to run away and for teleport it gives you an excellent chance to sneak attack on any champion.
For example: If you put a ward in the bushes and you see a enemy champion that might be good to kill that can't see you. You just have to teleport in the bushes and sneak attack on them. Also Kog always has hard time at the beginning, especially when fighting with long ranged characters. So it is great to have teleport to go back and forth from the base to the tower.

Before going into the skill sequence, I will explain the skills and the way to use them.

1. : A skill that is both active and passive.
This is a main skill for AD Kog. This skill reduces the enemy's magic resistance. So it gives a crazy amount of damage over the due of time with the other major skill Bio-Arcane Barrage.

2. : Active skill. SUPER important to Kog.
This skill is important for Kog, because without it, Kog will not deal as much damage as it should. If you are AP Kog, the percent of this will increase giving Kog a ridiculous amount of damage, but this is AD Kog. That is why we match Madred's Blood Razor Madred's Blood Razor. This item gives an extra 4% to this skill. So when the skill is mastered the total amount of percentage would be 10%!!!
Also this skill gives a ridiculous amount of range to Kog, and enemy champions have no chance against this attack. This is a prime reason Kog can do sneaky and shadowy attacks, because of his ridiculous range.

3. : Active skill
This skill is a good skill when ganking/chasing/fleeing. The damage it gives to the enemy champions isn't that much in AD Kog, but it has a great side effect. The slow!!! Also it is about 4 seconds unless the enemy has tenacy to slow and those things. In AP this is a great damage dealing skill, since it can come up to 800! damage. Yet in AD this skill should be used a little bit differently.
Normally people would shoot this skill at the enemy champion itself, but when AD, try to shoot to the side that the enemy would probably escape. The reason is because this skill doesn't do that much of damage and when they try to run away and the skill is just on them, as soon as they get out they can probably run away. Of course if you have a lot of damage and you are confident that you can kill the enemy champion it is ok, but normally Kog can't fight solo. So it is good to shoot it on the escape route and making a slow line just like Karthus' skill.

4. : Active skill
This skill works great with Bio-Arcane Barrage. The reason is because it shows the enemy hit by it for 4 seconds and is basically like a short ward. Also when you use this skill and the enemy is close enough you can shoot him/her with the ridiculous range you gain with the Bio-Arcane Barrage... even when they are hidden in bushes!!
Also this is a skill that is great to kill champions running away. Since this skill also has a monster range and a monster damage, if you are able to anticipate and hit the enemy champion well, you can get easy kills.

5. : Passive/Active skill
This skill is probably one thing that makes Kog so annoying in team fights. This skill lets Kog be alive for a few seconds after his death and explode after few seconds. The important part of this skill is that it deals REAL damage, which means that all the magic resist and armor of the enemy champion doesn't matter. Using this skill you can get an extra one or two kills after you die.

Skill sequence

I start Kog with Bio-Arcane Barrage. The reason for that is because Kog is slow and weak at the beginning, but you also need a lot of money for Kog at early time of the game. So with this skill I can shoot minions from far away and get the money required. After level 3, the skill sequence is concentrated on Caustic Spittle. The main reason for that is because at first a good attack speed will help Kog be safe and get more kills. The reason for not starting with Bio-Arcane Barrage is because you should not get really greedy with Kog, and this skill makes people get greedy over some not-worth-kills.
The next skill that you master is the Bio-Arcane Barrage. At this point the game is already reaching mid-game, so from now you need range and damage for team fights. You really don't need the Void Ooze very much for AD Kog, except for slowing down enemies, so that is why this skill is mastered at the end.

When using skills try this order.
1. Auto attack the enemy champion and make him come to you.
2. Use the Void Ooze at the expected path that the enemy will take.
3. Use Caustic Spittle on the enemy champion.
4. Use Bio-Arcane Barrage and just melt down the other champion.
5. (recommended) Use Living Artillery while attacking

In pictures.

Auto Attack -> -> -> ->

This is a very easy thing, but there is a key point to this. When playing AD Kog, the Ooze ball doesn't have great damage on other characters. Yet it has a great thing, which is the ability to slow. That is why you use it the path the enemy might take to escape, not on the character itself. So if the champion tries to escape, you can slow it down an kill him/her/it.

One last skill that a summoner's has to know properly is the passive skill. It is the ability to blow up after you die and this is a key point to Kog. You have to know how to die well, and also to be beneficial to your team after you die.

Item Sequence

I recommend to start with the Doran's Blade. Doran's Blade is always an excellent start with any AD character, and by this, the possibilities that Kog will survive at the beginning increases due to the extra 100 health.

As soon as you get 1000 gold go back to home and buy Madred's Razors. Even if you feel like you are getting slow, just buy this first. This item gives you more minion kills than you can imagine.
or
Then go with the Bersearker's Greaves and Phage. YET, if you get 1650 just buy B.F. sword. If you get 1650 again buy it again. But just twice. With Kog you will have to go back to the base frequently, so when you return try to buy an item. Two B.F swords at the beginning mid game will give Kog a monster damage over other champions.
=>>> Madred's Blood Razor
After the two B.F. swords or Phage and Berseker's Greaves complete make Madred's Blood Razor, starting with the Pickaxe and then Recurve Bow. It might seem that buying a Blood Thirstier or Infinity Edge is more beneficial, but Madred's Blood Razor is much more important than those two items. You can choose which you want to get first, the boots and health or damage. Yet buy the other items after buying either one of them.

Also it gets really easy to buy the Bloodthirster. You just have to buy Vampiric Scepter. At this point it is a good time to sell the Doran's Blade we had during the whole game. Since you get the necessary health and the life steal, it is not that much needed and it will give you more items space for other items.

Unfortunately, there is not extra space to buy the Cloak of Agility, so you have to buy the Infinity Edge right then. When you buy Infinity Edge, the items that is not completed is Frozen Mallet and Phantom Dancer.

First buy Zeal first. This item give Kog more movement speed and critical chance and a great attack speed. You could try to buy the Giant's Belt first, but about when you have to buy these items the game is already at the last part. So more health won't do that much of a deal due to the crazy damage the enemy gets. So that is why to get more control it is better to go for Zeal.

Now it is the time to get Frozen Mallet. Phantom Dancer costs less, but Frozen Mallet has an advantage that you can't ignore, which is... slow. By now Kog has about 1.7 attack per second. So you will probably slow down the enemy when they are running away. Then finish off the build with Phantom Dancer.

There is a big problem with this build and it is that......It costs about 18.5k in total. It is very expensive and Kog isn't the best farmer and even with killing other champions it is hard to get money. So probably you won't complete this item tree before the game is over. I played with this tree about 30 times and I completed it only about 2 or 3 times.


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If you can make to this build you will practically be super powerful. Yet the problem with this build is that it makes you extremely squishy. Although the Frozen Mallet gives you an extra boost of health and some armor, when any ap characters attack you, you become very vulnerable. That is why during the game you can change the item sequence in the way that you like. I recommend Hexdrinker . The reason is, because of Kog's fighting style. Kog deals a great amount of damage over a quite short amount of time, but when fighting an ap dammage dealer, you normally get to die really quick. So let's say that in a team battle the enemy's ap dealers take 4 seconds to kill you, do dealing an average of 500 damage per second. The time for Kog to kill any one character normally takes about 6~7 seconds(not tankers, they take more time). So normally you will die without killing anyone. Yet with this item it gives you a crazy magic resist for 4 seconds when your health is down to 30%. So now the enemy needs about 7~8 seconds to kill you too. So with a good amount of control, you can successfully harass the other team.

Runes for Kog is kind of the same with any dps. I gave Kog some beginning health of about an extra 78 health. With the doran's blade you start out with about an extra of almost 200 health, leaving Kog less vulnerable. Then the rest I gave attack speed so that Kog will be more annoying.

Laning:

Beginning->

At the beginning of the game, Kog'Maw is, as mentioned before, super vulnerable. Seriously, be a bit aggresive without any care and you will become a alien bomb. So my advice is so that you play safe and just farm. Of course if you are very confindent of your control then go ahead and be aggresive, but I think that you will die 9 out 10 times. Also a good partner while laning is a tanker or a champion with a slow/stun skill. The reason for this is because you want to be as safe as possible, but you do want to give some damage to the other champions. To do that you have to be someone taking all the attacks or someone who can stop the enemy attack.

Mid-Game

During mid-game is probably when Kog is the strongest. With his caustic spittle mastered and his attack speed about 1.5 per second, he can literally melt any enemy champion he wants. This is the time you want to get as much kills as possible, since after this time it gets harder and harder to get money. It is ok to die as long as you get enough kills when you die. For example, if you are in a team fight and you die after killing about one or two champions, be sure to use the icathiian surprise .

There is a reason I call this build the sneaky killer. This build is focused on mostly on melee attack so this means that one has to have an excellent control. But the thing is that what one should realize is that Kog has a crazy range. So whoever can use that range wisely can easily own other champs. That is why when the item tree is not completed it is a good idea to put down wards to be able to attack through walls and jungles.
Yet not all cases will let you be able to kill like a ninja, hidden in the shadows. In those cases, such as team fights, you have to be able to understand Kog's part in the team. He is a heavy damage dealer, both to squishy and tanky champions. At the same time he is an incredibly squishy fighter too. Even with 23% life steal(it is a good amount), Kog is very weak. The only reason for the life steal is to be able to regen health by going through the jungle. That is why when a team fight start, and don't start it yourself, stay at the back and either kill the other team's damage dealer that stays at the back or if there is none like that then aim for the tank.
Yup, the tank. This is because with Kog's Bio-arcane Barrage . With that skill and Madred's Bloodrazor you deal 10% of the enemy's max health. So this will help the team to be able to catch the hard tank with ease even if you die. And when you die, do not chase for the fleeing enemy. There is a possibility that you might be able to catch them, but it is way better to just try to deal as much damage as possible to many champs.

*1: When using Kog'Maw never engage in a one against one head to head fight. You will probably lose even if you get to kill the enemy champion. This is because Kog is pretty much squishy.

*2: When going into bushes use the Living Artillery in it before you enter. This action prevent you from going into small bushes that contain a huge amount of enemy champions in it.

*3: Like most champions, Kog is a champ that needs to farm. The more you farm with Kog, the stronger you become. So during lane fights, try to avoid as much conflict as possible and just safely farm.

*4: Try to know where the blind spots are. These blind spots give Kog a great advantage when fighting, and since people freak out when the see attacks coming from unexpected places, it is a good knowledge.

Kog'Maw is a very squishy champion, but he is strong and OP when used well. I personally think that if someone can play a good Kog'Maw, he can be a really annoying opponent. I mean, think about it, if you keep poking at the other team, that is gonna be annyoing