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Kog'Maw Build Guide by Vapora Dark

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League of Legends Build Guide Author Vapora Dark

Vapora's Guide To Kog'Maw

Vapora Dark Last updated on January 21, 2018
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Cheat Sheet

Kog'Maw Build

LoL Path: Precision
LoL Rune: Fleet Footwork
Fleet Footwork
LoL Rune: Triumph
LoL Rune: Legend: Alacrity
Legend: Alacrity
LoL Rune: Coup de Grace
Coup de Grace

LoL Path: Sorcery
LoL Rune: Celerity
LoL Rune: Gathering Storm
Gathering Storm

+9% attack speed and +10 ability power or +6 attack damage, adaptive

LeagueSpy Logo
ADC Role
Ranked #27 in
ADC Role
Win 49%
Get More Stats

Ability Sequence

Ability Key Q
Ability Key W
Ability Key E
Ability Key R

-Table of Contents-
About Me


Hey guys, my name is Vapora Dark. In season 5 I was Master tier EUW on 2 seperate accounts, in season 6 I climbed to Challenger rank 131 in 11 days on RU, and currently in season 7 I'm Master tier EUW. I main ADC and it's my most played role by far.

Kog'Maw has always been the clearest example of a hypercarry. He's an ADC with a weak early-game, who will scale into a late-game monster that can single-handedly decimate teams when given enough peel and protection. If playing for late-game is your style, then Kog'Maw may be perfect for you.

Let make it clear from the start that this is a guide to the high Elo way of playing Kog'Maw. And as such I'm going to assume throughout the entire guide that your support is Lulu. Why? Because Lulu is by far the best support for Kog'Maw and the difference between a Lulu buffed Kog'Maw and a regular Kog'Maw is like night and day. In high Elo I literally never see Kog'Maw being played with any support that isn't Lulu, and I don't pick Kog'Maw if I don't have Lulu as my support.

I hope you enjoy reading the guide as much as I enjoyed writing it, and most importantly, that you take everything you can from it!

If you like Kog'Maw and would enjoy talking about him, come participate in /r/KogMawMains on Reddit.

Follow me on Twitter.

Follow me on Snapchat @vaporadark

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Join my Discord server.

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Precision & Sorcery

Press the Attack
Press the Attack: This is the best keystone on every ADC right now. It'll give you a nice bit of burst as well as increase your DPS and increase your support's damage as well.

Triumph: This can be a life saver in close fights, and the 25g per takedown actually adds up to quite a bit in bloody games.

Legend: Alacrity
Legend: Alacrity: Almost all ADCs will want to use this rune over its alternatives since they all scale so well with attack speed. It'll ends up adding a lot of damage once you stack it up and have some AD and crit chance to pair it with.

Coup De Grace
Coup de Grace: This is the best rune in its tree for almost every champion that wants to go into Precision since it's the one that simply does the most damage in your average game.



Gathering Storm
Celerity: This gives around half the movement speed Boots of Speed does, which is pretty nice for a rune. It also has synergy with Zeal items and will give you just a tiny bit more AD, which can potentially be the difference between life and death.

Gathering Storm: All ADCs benefit greatly from extra AD, and Gathering Storm starts off kinda weak but really ramps up as the game goes on, and it shouldn't be underestimated how much of an impact a single point of AD can make in an ADCs kit.

Flash and Heal has been the standard ADC summoner spell combination since possibly mid-season 3. In fact, Flash has been the standard summoner spell to take on almost every single champion since forever. It's always been indisputably the best summoner spell in the game, so there's nothing you can replace it with.

Heal on the other hand, replaced Barrier when it got buffed in season 3 to give movement speed on the cast, which is the reason it's been standard over Barrier ever since, despite being affected by Ignite's Grievous Wounds. Aside from the small movement speed boost, which can be used both offensively and defensively, another reason why it's stronger than Barrier is it affects an ally, which is perfect for bot lane where you're laning with a support.

The reason you want a defensive summoner on ADC is that you have a lot of DPS, so the longer you can survive, the more damage you'll put out, usually out-damaging what you'd get from Ignite. And if it can go as far as to save your life, then that's even better, as ADC's are very important to have alive for both providing DPS and taking down objectives.
-Skill Order-

> >
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Icathian Surprise
Icathian Surprise: Do I even need to bother talking about this? With this guide you're never going to be using it anyway. :^)

But seriously there's not much to talk about here. When you die you just go full kamikaze, run around for 4 seconds then explode and deal strong true damage to anyone you hit. Once you've seen it once you already understand everything there is to know about it. The hardest thing about using this spell is to remember to start running towards an enemy as soon as you die, rather than standing up and smashing your keyboard against the wall like you usually would when you die.
Caustic Spittle

Caustic Spittle: This spell can feel pretty non-impactful, but the invisible contribution of its armor/MR shred can actually be pretty huge, especially on a tank. Try not to waste it just as harass if you're about to get into a full-blown fight, since there can be a pretty big difference between having or not having this up.

Additionally, Caustic Spittle passively gives you permanent attack speed, which is the main reason for maxing this second over Void Ooze.
Bio-Arcane Barrage

Bio-Arcane Barrage: The main spell that sets Kog'Maw apart from other ADC's. While active, Bio-Arcane Barrage turns Kog'Maw into one of the highest DPS champions in the game; while DPS'ing from 710 auto-attack range away.

This is even more important not to waste just before full-blown fights, since Kog'Maw with and without Bio-Arcane Barrage is like night and day. Without it, you do less damage than ADC Twisted Fate.
Void Ooze

Void Ooze: In the past Kog'Maw used to max this spell second for extra wave-clear. However, this isn't necessary anymore with the introduction of Runaan's Hurricane, giving him passable waveclear without requiring him to max Void Ooze second for it.

The damage this deals on AD Kog'Maw is negligible, so its main use is as a slow. Use it wisely; sometimes you may need to use it offensively to slow fleeing enemies, and others you may need to use it to help you kite or to slow enemy pursuers.
Living Artillery

Living Artillery: This spell doubles as semi-spammable harass (you don't want to spam it too much to not go OOM), and as an execute for fleeing enemies. When using it on low HP enemies it can also easily proc Stormraider's Surge to keep you chasing well.

Past Kog'Maw builds used to spam this in conjunction with Trinity Force to get a lot of damage out of Sheen procs, but the current Kog'Maw relies much more on pure attack speed for DPS and will only want to use Living Artillery in fights once enemies are out of range.
Doran's Blade
Doran's Blade: Doran's Blade doesn't build into anything, but it's one of the most cost-efficient items in the game, making it a great item to pick up early on when you're not going to be selling it any time soon. The HP makes you a lot more durable in all-ins and ganks, helping you to survive in any scenario where the slow-acting sustain of having extra pots wouldn't help you.
Guinsoo's Rageblade
Guinsoo's Rageblade: At full stacks, this item gives the most attack speed in the game, making it a perfect fit for Kog'Maw who has the strongest on-hit in the game in Bio-Arcane Barrage and therefore benefits immensely from attack speed. The other stats are also good on Kog'Maw since AD further increases the strength of his auto-attacks, and every spell in his kit scales with AP. The on-hit is also very good on Kog'Maw as he builds so much AS, and the Guinsoo's Rage passive likewise is very strong on him due to all the on-hit he has. This will generally be your first item since it's such a huge powerspike, but you may also situationally rush Wit's End instead.
Berserker's Greaves
Berserker's Greaves: Since Kog'Maw scales so well with attack speed, these are the obvious choice of Boots. It's generally smart to pick them up early on if you back on not enough gold to finish your Guinsoo's Rageblade, provided you've already built Recurve Bow; since they give so much attack speed and the mobility can easily be the difference between life or death, whether for you or for enemies.
Runaan's Hurricane
Runaan's Hurricane: Whether you build Guinsoo's Rageblade or Wit's End as your first item, Runaan's Hurricane will always be your second item (not counting boots), as combining it with either Guinsoo's Rageblade or Wit's End provides you with a lot of AoE DPS.
Wit's End
Wit's End: You can rush this instead of Guinsoo's Rageblade if you need the MR to help you get through a high magic damage lane, such as when laning vs Zyra support. It's much cheaper so it's also going to be a much quicker powerspike for you in lane, which is all the more incentive to rush it even forgetting about the MR it gives. Even if you're not rushing it, it can still be situationally bought instead of Blade of the Ruined King if you find yourself needing MR at that stage of the game.
Blade of the Ruined King
Blade of the Ruined King: If you're rushing Guinsoo's Rageblade then this is the item you'll usually want to build after you have Guinsoo's Rageblade, Berserker's Greaves and Runaan's Hurricane. It offers even more attack speed, some lifesteal and more precious on-hit to synergize with all the attack speed you have.

At this point in the build I need to pause and explain the thought process behind the next item options. It may seem logical to keep building attack speed (why not have Guinsoo's Rageblade, Runaan's Hurricane, Blade of the Ruined King and Wit's End all in the same build for example?), but pause to think about all the attack speed buffs you're already getting: Guinsoo's Rageblade, Runaan's Hurricane, Blade of the Ruined King/ Wit's End, Berserker's Greaves, Caustic Spittle, Whimsy, and Ardent Censer.

At this stage you're going to spend a lot of time at the attack speed cap, and so building any more AS/on-hit will greatly go to waste. At the same time, lifesteal isn't too valuable because most of your damage is on-hit rather than your actual auto-attacks, and armor pen is useless since you actually deal more magic damage than physical damage. On the other hand, your damage output is already insane, and all you need to do is stay alive in team-fights long enough to decimate the enemy team.

So this is where the meta Kog'Maw build starts to instead focus on building defensively rather than more attack speed/damage which is considered ineffective/wasted.
Frozen Mallet

Frozen Mallet: 700 HP goes a long way towards making you more durable, and the 30 AD will slightly increase your damage output in a way that doesn't go to waste as more attack speed would. More important than the AD though is the slow, which is incredibly strong both defensively, to increase the effectiveness of your kiting, and offensively, to chase down slowed enemies alongside Whimsy and Stormraider's Surge , who will find themselves having to Flash away from Kog'Maw or die if they ever make the mistake of getting too close to him.
Mercurial Scimitar
Mercurial Scimitar: This is a great item to deal with CC on the enemy team if they have it. Again, AD is a nice way of increasing your damage out-put in a way that won't go to waste like AS would, and the lifesteal isn't unwelcome either. If you know how to use it and have the need for it, then Quicksilver Sash/ Mercurial Scimitar is an amazing item, but it's situational as you may not always find a need for it in every game. But sometimes you may also need to build Quicksilver Sash much sooner than as your 5th item if it's sorely needed against something like Infinite Duress or Nether Grasp.
Guardian Angel
Guardian Angel: This is a very good item when you know you're going to have a hard time surviving team-fights. You can build Chain Vest sooner if the armor is really that important. The same doesn't go for Negatron Cloak as Hexdrinker is a more effective solution for high magic damage.
Maw of Malmortius
Maw of Malmortius: A very strong defensive item when you're taking heavy magic damage in fights. You start off with Hexdrinker and can build it as your 5th item then build a 6th item before upgrading it to Maw of Malmortius if it's more important for you to finish the rest of your build.
Sterak's Gage
Sterak's Gage: Adding this on top of Frozen Mallet makes it extremely hard for enemies to burst you down, making this the ultimate "**** you" to champions like Rengar.
Infinity Edge
Infinity Edge: If you really feel like one defensive item is all you need, you can add this to your build since it's the biggest damage item you could build at that point. However, it's not as big a powerspike to Kog'Maw as it is to other ADC's since most ADC's build damage through auto-attacks while Kog'Maw builds on-hit which is unaffected by Infinity Edge, which is the reason why you'll be dismissing it most games.
Early Game
You'll want to take Bio-Arcane Barrage at level 1 since the increased range and damage of your auto-attacks allow you to trade more effectively, and it'll help you outpush the enemy bot lane as you race for the first level up.

When you get into lane, you should spam auto-attacks to push as fast as possible to beat the enemy bot lane to level 2. You can try and poke the enemy ADC with free auto-attacks if a good opportunity arises, but for the most part you shouldn't be actively seeking these and should instead just focus on pushing faster than the enemy bot lane.

Whichever bot lane starts losing the push should begin to back off once they've clearly fallen behind in the push, to avoid trading against the bot lane with the minion advantage. As Kog'Maw you're one of the slowest level 1 pushers and will frequently find yourself losing the race. You should back off when the enemy bot lane is approaching level 2 so as to not die or take a bad trade, and just allow yourself to be zoned until the wave pushes into a better position for you or you hit 2 yourself.

However, undoubtedly you will sometimes find yourself winning the race to level 2. At this point you don't want to keep pushing, but rather begin to freeze by only auto-attacking the minions to last-hit. This is for two reasons: the most obvious reason is that when your minions get low from being auto-attacked by the minions you're intentionally leaving alive, the enemy ADC has to walk towards you if they want to last-hit it and take free poke in exchange, and rather than do that they will instead choose to miss that CS, placing you at a CS advantage. The second reason is that while you want to push for your level 2 powerspike, your level 2 powerspike is useless if you push the enemy bot lane safely under tower. You want the minion waves to stay as close to the middle of the lane as possible, so that when you hit level 2, if the enemy bot lane don't let themselves be zoned far enough away you can jus tall-in them for a kill, or at least chunk them for a lot of damage. Good minion wave management at this stage will have you winning the level 2 race without the minions budging from the very middle of the lane until later.

Throughout laning phase your win condition will usually be to sit back and passively farm up, as you'll usually find yourself on the losing side of the matchup. This won't be much of a problem though as you have 2 different skillshots to help you last-hit from a long distance if necessary, and Help, Pix! will keep you from taking too much damage as the enemy bot lane attempts to bully you to shut you down.

When you're on the winning side of the matchup you should instead however focus on shoving the enemy bot lane under tower (with enough vision to keep you safe, otherwise freeze or let them push you in). Bio-Arcane Barrage will allow you to bully the enemy ADC under tower as they go for last-hits, from a safe enough range that you can consistently avoid taking tower aggro.

Whenever you're shoving under tower and can't poke anyone with auto-attacks, you should be auto-attacking the tower to make sure it goes down as soon as possible, since it's a +650g boost in power for you if your team allows you to take full local gold (as they should).

Out of Lane

Outside of laning phase, your objective is to destroy the nexus. No I'm not kidding, that's literally the best way to describe it. Every action you take in laning phase is to set you up for mid-late game, every action you take outside of laning phase is to bring you one step closer to destroying the enemy nexus. The way you do this is by performing actions that will make killing the enemy team easier (acquiring gold, dragons, barons) so that you have less resistance, and destroying towers as a way to acquire gold, have better control of the map, and open up routes to the nexus.

At this point you should be grouping with your team as much as possible to teamfight and siege down towers. Kog'Maw is a fairly good sieger due to his extremely long auto-attack range with Bio-Arcane Barrage, as well as the presence of a Lulu to buff him up with Whimsy to keep him safe.

Sieging towers is pretty simple, but you need to be careful about it. When both teams are alive and your team is trying to take a tower, it's your job to do as much damage as you can to the tower without dying. You need to do as much damage as you can while remaining safe. This means you can't just walk up to the tower and stand there auto-attacking until it dies; this leaves you open to get engaged upon, unless there's no resistance from the enemy team. Instead you have to repeatedly poke the tower. Walk up to it, attack it a bit, back off if someone dangerous is walking up to you. Now you might think "but what if they never stop protecting their tower? Doesn't that mean it's never safe for me to auto-attack it?". If they're constantly standing in a defensive position in relation to their tower, then they're most likely to be in range for your team to poke them and force them back. They need to be in a place where it's safe for them to sit and look for a good engage, where your team has no way to attack them without tower diving them. And if they advance, that takes them further out of safety, so if you match their movements to stay safe from an engage, they'll be forced to move back for their own safety again, as they don't want to get engaged on in a bad position either, nor poked down to a point where they need to recall to recover their HP.

So you should think of sieging as slowly whittling down a tower. It almost never takes a single minion wave to destroy a tower (unless you have baron buff), it can take many, many waves, but slowly but surely, the tower will go down if you can siege it properly.

When you're attacking a tower with enemies nearby you always want to be positioned at max distance from the tower while you auto-attack, and in between auto-attacks you should move backwards then forwards, so that while your auto-attack is "on cooldown", you're not spending any more time closer to the danger than necessary. It's also good habit in case they start to try an engage and you're already automatically moving backwards the moment you finish your auto-attack, meaning you'll often protect yourself from an engage faster than you can actually react to it, so long as you notice in time to not move back towards the tower for your next auto-attack.

Against teams with very high wave clear, it can be very hard if not impossible to siege down towers, especially inhibitor towers that actually recover HP all the time. Your options in these situations are to engage on the enemy team under their tower (which only works when you're reaaaaaaaally far ahead), get another lane to slow push then rotate to it when the wave is reaching the tower, or go get baron. The enemy team won't usually just give up baron for free though, and so you can use this to bait them into a fight. They'll need to constantly have vision on baron to make sure you're not doing it, which can be hard to keep up if your team places Control Wards and uses Oracle Lens to clear their wards, so at some point they might have no choice but to face check baron to make sure you're not doing it. Even if you are, you can take the opportunity to turn around and team-fight, so long as your team hasn't become too low to fight.
Ever wondered how pros can get 300 CS at 30 minutes before? No, it's not completely down to "insanely good last-hitting mechanics". You can do it too, just by using a simple wave control technique. Watch this video to understand how minion waves work.
So when 2 minion waves collide on bot lane, in the middle of the lane, you should be there to push those 6 minions. And then you leave bot lane. No, you don't stay to push the 2nd minion wave too and force your wave to hit the tower. Aside from being at risk if you do that, it's also just not smart to do it. Because once you clear the first wave and your minions advance to crash into the next minion wave, your minions will be on the enemy's side of the map, and as you just learnt from the video, that means that the wave will slowly but inevitably start to push towards your side of the map.

After clearing that first wave you just go pressure mid or teamfight or whatever, then you just return bot lane in 2-3 minutes when the enemy minion wave has finished pushing to your tower (and make sure to get there before the minions start dying to the tower). At that point it'll be a 15-20 minion wave. Assuming it's 20 minions, and you've been off of bot lane for 2 minutes, you'll be getting 20 minions for the 2 minutes you've spent off lane, keeping with the 10 cs per minute rule you always want to aim for (though won't always be able to achieve).

But even if it isn't quite 20 minions, the time that you've spent off of bot lane, you'll have spent farming mid lane, and maybe even jungle monsters. You'll essentially be farming 2 lanes at once, keeping you easily above the 10 CS per minute rule so long as you can consistently get to the bottom lane wave in time before the minions start dying to the tower. This won't always be possible, as CS isn't the most important thing in the game. Sometimes you'll be busy teamfighting, or making sure you're around in case a teamfight starts. But in general you'll want to go farm the wave as much as possible, then push the wave onto the enemey's side of the map to restart the push, both to get ahead in farm and to avoid having a huge minion wave destroy your tower.

When the wave that you're pushing is a cannon wave, that messes with this technique a little bit. Because you'll be killing the enemy cannon minion and letting your own cannon minion push uninterrupted, the enemy minion wave won't slowly push up to your tower. Instead your minions will continue to push forwards, very slowly. When it's a cannon wave, you should either push the 2nd wave too (if it's safe to do so, not at all safe to do when the enemy team is ahead in towers and enemy threats are unaccounted for on the minimap), or just recognize that you won't be able to get the wave to push back to you in this specific situation and settle for creating a slow push instead, rather than trying to create a farming opportunity for yourself later on.

The video also explains how to create a slow push, but this technique is very rarely useful in solo queue with how uncoordinated everyone is outside of very high Elo. Keep it in mind in case you ever think it could be useful, but most of the time it just ends up creating a huge minion wave for the enemy AD carry to farm, getting him ahead in farm instead of you. It's better suited for ranked 5s assuming your team understands the strength of a slow push, or if you're a high Challenger player and for some reason reading a MOBAFire guide.

In some situations, notably when you expect to be sieging for a while and especially sieging towers that are really close to the enemy base, such as inner towers and inhibitor towers, it's really not ideal to have to force yourself to go back bot lane to farm every 2 minutes. If you do the technique and you can't go bot you'll essentially have just created a slow push against yourself, causing the enemy minions to die to tower, wasting gold, damaging your tower, and possibly even destroying it. Rather than putting yourself in that situation, this is when you want to create a slow push against the enemy team, as they'll hopefully be too busy defending against the siege to send someone to clear bot. This way they'll be the ones losing minions to the tower, taking tower damage, and possibly losing a tower if it's already low. And if they do send someone to clear it, you'll either have an easier time sieging or your team will be able to dive the enemy team 5v4 under tower.
When it comes to team-fighting as an ADC, there is one golden rule which is the most basic team-fighting rule of all, and yet makes you an infinitely better team-fighter if you start following it; attack whoever's closest to you. If you stand at the back, behind your frontline, and just auto-attack whichever enemy is absolutely closest to you, you have the best possible positioning, as you'll only be in focus range of whoever's diving you, or whoever you're attacking. It's recommended in general to take down the enemy carries before the tanks, but as the ADC if you try to attack a carry then you're in range of every single member of the enemy team, and if they all focus you then you'll go down in under a second. By keeping your distance and attacking just whatever's closest, you'll be hardest to kill, and can therefore output maximum DPS by just staying alive and being able to auto-attack all fight long. The only time you should attack the enemy team's carries is when there's no other enemies standing between you and them or if they're horribly positioned themselves and you can focus them down along with your team.

The best players of all know not only when to follow that one basic rule, but also when to take even further measures to stay safe. Before you ever even get into a team-fight, you should have already analyzed what all the threats to you on the enemy team are, and play more safely or aggressively accordingly. For example, if a Shyvana is the one trying to dive you, you'd want to follow the rule of attacking whatever's closest, and just kite her while your team also hopefully tries to peel her.

But sometimes you need to turn the safety notch up another level and straight up walk away from someone that could be a threat to you. For example, if you're playing vs Zed, you cannot be one of the ones trying to focus him down while he still has enough spells and HP to be a threat. Even if he's the only person in range of you, and you have 3-4 team-mates around you, you still can't be auto-attacking him until the threat he presents has been neutralized ( Death Mark goes on CD, or he gets so low that he'd die before he could burst you). All the skill and mechanics in the world won't stop him bursting you down in half a second if he gets near enough. And you not only need to stay out of his Death Mark range, you also have to account for the extra distance he can cover with Living Shadow, Youmuu's Ghostblade and Flash, and how quickly they can help him close the gap.

No, when you're playing against Zed and you see him running in your direction, you stay as far away from him as you can get. Don't help your team kill him, that's not your job. The assassin's job is to kill you, your job is to not die to him, and your team's job is to protect you from assassins by killing them. If the assassin commits their cooldowns onto someone else when they realize they can't get to you, that's when it's safe for you to walk back into the fight. Or if the assassin gets CC'd and blown up uselessly before they get to do anything, then it's also safe!

Champions that present such a large threat to you aren't just limited to assassins ( Talon, Zed, LeBlanc) that can burst you down within a second. Other champions, mostly if fed, can just out-duel you so brutally, that even if you have 2-3 team-mates helping you in an effective 1v3/1v4, you're still going to die if they can get in range of you. Champions that can commonly do this when fed are bruisers like Irelia, Jax, Renekton, etc. Champions tanky enough to qualify as tanks while still dealing huge damage to a squishy target like you, especially when fed.

Against champions like these, it's really necessary for you to watch out and keep your distance. You can throw Void Ooze and Living Artillery at them, but you can't fully commit to DPS'ing them down until again, they either fall so low at your team's hands that they're no longer a threat, or realizing that they can't get to you, they commit their most important cooldowns (mobility and/or CC) onto someone else. In Irelia's case, it's safe to commit onto her when she's used either Bladesurge, as she won't be able to gap close to you or burst you with it (though Flash may still pose a threat), or Equilibrium Strike, as it'll prevent her using her deadly 2 second stun on you. And if she's used both then until they come off of cooldown she presents almost no threat at all, so long as you maintain good positioning and kite if she tries to walk towards you.

When following the rule of "attack whoever's closest", often you'll have to choose between two champions that are at a more or less equal distance from you, and it'll be optimal for you to attack one or the other, but it's hard to be completely certain about who the right target is. That being said, here are some things for you to consider which will hopefully lead to you making the right choice:

1) Which is the bigger threat?
You'll want to take out whoever's the biggest threat not just to yourself, but to your team as a whole, and disregard the weaker enemy. Sometimes it's not very clear cut, others you have to choose between a fed Riven and a 1/1/5 jungle Sion, in which case it's a very obvious choice which you should focus.

2) Who would die faster?
When the targets are equally threatening, you'll want to focus whichever one is squishiest/lower HP, as the sooner they're out of the fight, the sooner your team gains a numbers advantage. Sometimes even if they're the lower threat, it's still worth focusing them down first if they're going to die significantly faster, but only sometimes, and it depends on how big a threat the other possible target is.

3) Who's least likely to get away from you?
The less mobile one is the least likely to walk away and succeed in getting away. You'll want to focus the least mobile one as they're the ones most likely to die if they get low. A tank with gap closers like Zac (and let's just say his passive isn't up so you don't need to worry about that) may get low, then just leave the fight with Elastic Slingshot before you can finish him off. If your other option is an equally tanky Sion for example, he's less likely to be able to get away alive when he gets low, so it'd be smarter to focus him in a situation where it's just as easy to auto-attack both.

Generally, from top to bottom those would be the most important factors to take into account respectively, but sometimes one factor, if it's big enough, can over-ride a generally more important factor. For example, choosing to DPS down a negative KDA, full AD Lee Sin, over a fed Irelia, because you can kill the Lee in about 2 seconds while the Irelia is a lot tankier, so takes a fair while longer to kill.
Hopper is Bae
That's it for my Kog'Maw guide. I hope you found this helpful and learn to play Kog'Maw as well as you want to.

If you enjoyed this guide you may also enjoy Vapora's Guide To Tristana, a guide to one of my favourite ADCs. They have different playstyles but I find Tristana fun to play as well. Otherwise you may still want to read it if you're wanting to improve your ADC skills because it's kind of like a general ADC guide as much as it is a Tristana guide.

Special thanks to Hopper for doing the banners and most of the coding. (Go check her shop out!)

If you're interested to see me play, follow my stream! Right now when I'm tryharding I pretty much only play Twitch, but if you would like to see me play any other ADC within my champion pool then let me know in the chat and we'll see if it's possible!