Hello there guys, I've been playing Kog'maw a long time. Kog'maw is a great and fun AD Carry. This is my first guide ever written and I am not an english native speaker, so please go easy on me with rude spamm comments. I will try to keep this guide as short as possible. It will propably be good for advanced players.

Usually you should pick Kog'maw when the other team has a tanky team (%dmg from W) without many champs who can jump you over the defensive lines or focus you out. (E.g. Akali,..) Because Kog'maw has no escape abilitys except his (E) (**** on the Ground). Enemys who can just jump over that and deal some dmg will most likely kill you.

EARLY GAME:
In early game it is important, that you dont take too much DMG, because you are so squishi, fat slow and have low attack range. Don't take to many hits and try to farm with your (W). Use it as often as you can since it has no cost. You might also think about harrasing the enemy ADC with your W, and E combo.

FIRST BACK:
It comes to the point, wher all your pots are gone, and you think "I might make it for another wave". But I can tell you, you won't. Every jungler is happy to gank you, because you are an easy target without an escape. So just go back and buy your B.F. Sword.

IMPORTANT THING IN LANING PHASE: Make sure you always have your lane warded. If the support doesn't you might wanna think about investing some gold into your own safety. Again: You have no escape.

Level 6:
Congrats, you are level 6, now you are a very annyoing Opponent, use your (R) and your (W) in Combination with your (E) to harras your Opponents, (****, on the ground and let the Cu.. Umm The "Acid" rain on your enemys.)

Teamfights:
In Teamfights it is important that you try to stay behind the defensive lines and kill the enemy teams ADC or APC as soon as possible. In anycase you should use your E to slow the enemy team and to ensure they cannot engage you. Vision is the Key to succes here.

The old Discussion: BORK or Bloodthirster:
I used to go for BORK and Attack Speed on Kog'Maw. Problem with this is: Every enemy ADC will crush you with some crits. The Solution: Get crits as well, get Bloodthirster (which gives way more dmg to increase your crits) and shoot the enemy ADC to death before he can get to you. Moreover Bloodthirster gives you more HP and more surviveability. (of course you might kill the enemys tank a little bit slower, but that is not really something to worry about)

Of course this guide is not close to being complete but I dont have much time to work on it right now (wirtten in 20 mins so far)

Hope you still like it!