Kog'Maw Build Guide by Aqua Dragon
Diamond AP Kog'maw - Acid Reign
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+9 Adaptive (5.4 AD or 9 AP)
+9 Adaptive (5.4 AD or 9 AP)
Champion Build Guide
Hi! I’m Aqua Dragon. I've been in Diamond for multiple seasons and I play AP Kog'maw.
I also play:
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- Gets exponentially stronger as the match continues
- Prevents damaged opponents from fleeing fights
- Reliably farms creeps from a distance
- Durable due to several HP-granting items
- Able to duel anyone late game
- Powerful objective defender
- Atrociously weak early game
- Has low mobility
- Low impact until Level 11
- Damage is sustained rather than bursty
- Pathetic objective controller
- Neverending greed for mana
Distributing Death in Moderated Concentrations
"Barrage Limit" is a term that will be repeated throughout the guide several times, and for good reason! It’s a fundamental part of playing AP Kog and impacts laning, teamfighting, and defending.
The ultimate’s mana cost goes up almost exponentially. Shooting 1 ult is a pitiful 40 mana, but shooting a full barrage of 10 bullets requires an enormous 2,200 mana.
This poses a problem. Continuing to fight requires constantly shooting, but constantly shooting drains mana. To maximize your time poking, you need to shoot just enough that your mana regen will have replenished more than the mana expended when your artillery stacks reset to 0, accounting for ult cooldown and Tear's mana refund.
Or, more simply:
The number of bullets it takes to break equal with your mana regen is what I term as the Barrage Limit. The two examples above have Barrage Limits of 2 and 3.
It's a bit more than 10 seconds because the ult does have a 1-2 second cooldown between shots, and there's also time needed to line up the next shot.
Your Barrage Limit can be considered your guaranteed bullets. The rest of your mana bar is considered reserve bullets. The Barrage Limit eventually becomes instinctual, but initially requires a lot of conscious thought. Your Barrage Limit starts at 1.
A final note: the Barrage Limit is not an exact science. You'll often find that you will lose 20-60 mana per barrage even if you stay at the Barrage Limit. However, it functions as a serviceable estimate. You can find out how to increase the barrage limit later in the guide.
Making the Rain Have Pain
There are a few extremely important, unintuitive things to keep in mind about AP Kog’maw for this guide to be of maximum effectiveness.
Scroll to the bottom of this section if you want the short version.
AP Kog’maw is largely a misnomer. Unless you’re at full build, your AP levels will hover around 200 AP even 40 minutes into the game.
This is because Living Artillery has a fairly unimpressive 0.35 scaling on it. The AP scaling does increase as the target gets lower health, but so does the base damage, meaning the AP-Base ratio stays awful. This makes AP an underwhelming choice compared to adding additional burn damage, increasing the Barrage Limit, or getting magic penetration instead.
To verify this, I ran a number of tests in the Practice Tool. The results: raw AP items like Rabadons, Ludens, and Horizon Focus weren't even close to matching the ult damage output of Liandrys, Demonic Embrace, and Void Staff, even on targets with only 60+ MR.
This isn’t to say Kog has bad ratios on their non-ult abilities; the other abilities have decent to good ratios. But AP Kog’maw is not dangerous due to their basic spells. If you’re looking for a mid-range AP champion, there are a wealth of others with significantly better damage, mobility, and utility.
Maximizing the base damage of the ult requires maximizing base damage, magic penetration, and the Barrage Limit instead.
Hitting a person in a teamfight with one Living Artillery is easy. Hitting them reliably again is hard. The ultimate is designed to be entirely avoidable. Even if a champion is directly at the center of the ultimate, they are almost guaranteed to be able to run out of the AOE.
This means Living Artillery is at its best when someone is running away, forced to either stop moving or to get hit. But there is a casting time, and so they will outrun you as the casting time of the Ult prevents you from catching up.
To reliably chain ults on opponents requires mobility or CC. Reliably chaining ults dramatically increases fighting power. However, when you hit the point where you can outrun opponents while ult’ing, any additional mobility encounters diminishing offensive returns.
Earlier, the Barrage Limit was discussed. Namely, that flat mana only increases reserve bullets. With just Tear, there is usually sufficient bullets in reserve for most fights, as long as the Barrage Limit is not constantly exceeded. This make flat mana a less worthwhile priority; it only is used when really pushing the limits of the ult.
Mana regeneration is great, but there are essentially no items that provide it in a significant enough amount. Any mana regeneration needs to be sought out in other ways, primarily through the Aqua Dragon Soul and Blue Buff. But when these are acquired, AP Kog gets some very noticeable power. Every time you increase your Barrage Limit, you effectively increase your consistent damage output.
For itemization, this mostly means that building flat mana, for the sake of more mana, is not worthwhile until much later.
Maximizing the power of the ultimate is the primary objective, and unfortunately, ability haste fails at improving it much. Because the 10-second lockout at the end of the ult does not change with AH, all AH does is marginally increase how fast the ult shots go out.
AH is useful for the other three abilities, but none of the three are good enough to justify investing too much itemization into. They aren't often used off cooldown in the first place.
CDR is still a decent stat, especially very late game, but not a high priority consideration.
Kog should be built to take maximum advantage of their high base damage, hefty range, and Barrage Limit. This means the stats Kog generally wants more than anything else are:
This guide is built around this mantra.
Take note this means you won't necessarily have a lot of early-mid burst damage. But this is okay because AP Kog is a sustained damage champion! Always remember this. You will often get comments like "you don't do any damage." This is because it is extremely easy to overlook sustained damage compared to burst damage.
You will almost always have one of the highest damages dealt in each match, so don't focus on the comments and focus on your aim.
Void Ooze makes sense as a first max for its powerful waveclear and increasingly nasty slow. It also has the highest raw damage output besides Living Artillery.
AP Kog is able to get off some reasonable autos so it seems tempting to max Bio-Arcane Barrage next, but this is a trap. Here's some numbers.
Bio-Arcane Barrage offers 3% max health damage on-hit at rank 1, increasing to 7% at max rank. In addition, without an AS item, AP Kog has a little under 1 auto per second.
So what’s the DPS increase from rank 1 to rank 5? Well, 3% of 1000 HP is 30 damage. After 5 ranks, this damage increases up to a whopping... 70 damage. Which means for four rank ups, that’s an increase of little under 40 premitigated DPS.
If the target has 3000 HP, that DPS bonus goes up to 120 DPS, which sounds great, but it’s also competing against Caustic Spittle’s three benefits from rank 1 to 5:
- 200 extra base damage (more burst)
- 20% bonus AS (more DPS)
- 8% stronger Armor / MR shred (more teammate damage)
Kogulated Rune Choices
Unsealed Spellbook beats the keystones of other trees (this is addressed further, below this rune choice section)
Magical Footwear handily stomps the alternatives, no contest.
Biscuits extend the laning phase, drastically increasing gold and EXP gain.
Cosmic Insight is generically useful. After much testing, I couldn't get much value out of Approach Velocity comparatively.
The resolve tree is chosen because the other trees don't provide enough impactful minor runes (detailed further below). Of the Resolve options, Conditioning is the main reason to go Resolve.
Overgrowth's raw reliable HP bonus is more impactful than the situational bonuses provided by the other Resolve choices.
Ability Power, Armor, and Magic Resist
Following the priorities listed in the Critical Knowledge section provides us these choices.
If these rune choices seem strange, you're right! Isn't this an AP Build?
These choices make much more sense if you go back a bit to the Critical Knowledge section. Those priorities are being put into practice here. As a reminder:
Let's take a look at the trees using this metric.
Many of the runes involve giving ability power. But as detailed in the Critical Knowledge section earlier, raw AP isn't a great stat on AP Kog overall.
This indirectly hits Arcane Comet too, which has a very weak base damage of 30-100 with a 0.2 AP scaling. Without burst or without AP, it is a very middling rune, rarely being the reason that many kills end up being secured.
Meanwhile, Transcendence offers AH, which isn't a stat that AP Kog wants either.
Scorch does add base damage by comparison, but it's clear that it is intended for lane harass and not for sustained poke. For sustained poke, it adds an awful 1.5 - 3.5 pre-mitigated DPS. Ew.
Celerity is very meh on AP Kog, who will get only a pittance of extra movement speed from the boot bonus and nothing else.
Manaflow band looks super tantalizing. 250 mana and 1% missing mana per 5? Doesn't AP Kog love mana?
More mana regen is nice, but let's put this into perspective. ~5 mana per second, at best, isn't even close to increasing the Barrage Limit a single time, making it mostly negligible for improving the number of Living Artillery shots. The flat mana is convenient for reserve bullets, but Biscuit Delivery conveniently gives a similar 150 mana!
This rune initially looks very tempting for the extra mana regeneration it affords, but quick testing reveals that it actually restores overall less mana than even Manaflow Band on AP Kog, which itself wasn't even good enough.
This is mostly because AP Kog's main interaction with opposing champions is through Arcane Barrage, which scales in cost so fast, Presence of Mind can't add enough mana during those harass windows.
Worse, the other Precision runes ( Coup de Grace, Legend: Alacrity, and Legend: Tenacity) scarcely do anything for AP Kog. Unless Presence of Mind is exceedingly good, it can't justify a whole subtree by itself.
Everything boils down to this: Manaflow Band and Presence of Mind are the only worthwhile runes in their respective trees for AP Kog, and even they're just mediocre. Even their keystones are meh. This easily makes Inspiration the primary tree of choice.
The mana regen offered by both these minor runes must then be weighed against the significant effective HP granted by the two Resolve runes. Consider that neither are even enough close increasing the Barrage Limit by 1, and it becomes more clear why Resolve is the secondary of choice.
There are too many flash-combos that even your max range can’t protect you from. Flash helps equalize the field.
When flash is on cooldown, this is your second equalizer against flash-combos. It also makes it exceedingly hard to get tower dove. AP Kog's whole paradigm is surviving through the early game, which Barrier solidly assists with.
All three are useful too, but Barrier is more useful during the laning phase.
The movement speed bonus from Ghost doesn't help for early lane survivability, and for a similar reason the movement speed bonus from Heal doesn't justify the higher cooldown. Exhaust is excellent for survival, but mathematically its damage reduction isn't as impactful as the Barrier shield early, mainly when at low health.
All three are great options to switch to with Unsealed Spellbook however.
If you’re in range to Ignite, you shouldn’t be.
Priorities in Practice
At the beginning of the guide, we established the priorities Kog has.
I also combined this with ample testing to find the most damaging items for AP Kog's Living Artillery. The build order is the culmination of all that.
We once more allude to the priorities mentioned at the beginning of the guide.
This order was not constructed arbitrarily, but was rather the result of extensive testing in Practice Tool to find the best consistent damage output on Living Artillery. The results? Magic penetration is absolutely amazing. There is no raw AP item that provides more power than magic penetration items on AP Kog'maw, even at low MR.
The following item choices were evaluated accordingly:
A large mana pool is important to make sure reserve bullets are always ready later in the game. Tear also lets you start with the Barrage Limit at 1.
The raw damage offered by the burn, especially over a barrage-over-time, makes Liandrys the absolute ruler of sustained poke DPS, even with the wasted Haste.
A mixture of magic pen and mobility, a godsend for Kog’maw. It's tough to imagine any better combination that Kog would like.
After testing a number of different items, Manamune was the clear winner in overall barrage damage. Nothing even came close. It's not as much bonus mana as Seraph's Embrace, but the Shock passive and bonus AD (which the ult scales with) add so much damage compared to the alternatives, it isn't even a contest, especially since Kog will have Muramana ready by the time Manamune is built.
Allows access to chaining, making teamfight power significantly scarier; essentially guarantees follow-up shots by boosting mobility in offensive situations.
Generally you want to avoid being the purchaser of GW, as the AP is a very low priority on AP Kog. Still, sometimes, it has to be you. Purchase where appropriate, and don't be afraid to just sit on Oblivion Orb for a while.
The next-best damage item, uncontested after you already have the combo of Liandrys and Muramana. Already better than every other item on any target with 50 or more MR.
Only slightly behind Void Staff in terms of added damage, but with the bonus of some health, MR, and armor, which AP Kog appreciates quite a bit. A nice alternative if maximum (but still potent) raw damage isn't strictly needed.
The common theme of this guide is that AP really is not that valuable on AP Kog. Rabadons exemplifies that; it is less damage-efficient than Liandrys, Void Staff, and even Seraph's Embrace. It's a terrible buy in all practical scenarios.
This exclusion may seem initially unintuitive, but becomes apparent after a major consideration: AP Kog scales poorly with AP, causing Muramana to deal substantially more damage than Seraphs. This means the predominant reason for getting Seraphs is the maximum mana, but the sheer damage added by Muramana overshadows the flat mana increase, which is only occasionally dipped into when exceeding the Barrage Limit.
The damage efficiency is so terrible that it severely gimps power. Plus, with a six-item core, there's no room for Banshees without delaying damage immensely.
Tempting as a final item instead of Void Staff, but even accounting for the added on-hit damage, it still deals less autoattack-DPS than Void Staff (though just barely). Worse vs tanky targets than Void and awful vs further-ranged squishies.
The damage isn't good enough to justify getting. Without a lot of AP, there's not a lot of additional damage being added on. It's less damage efficient than Nashors, which itself isn't damage efficient enough.
Magic penetration is higher on the priority list. Rylais is usually enough offensive mobility.
That's Off the Chain
When Kog has Rylais, they gain access to one of their most powerful and flashy tricks: chaining.
Chaining is using CC to ult a target back-to-back with Living Artillery.
Normally, chaining is hard. An opponent is able to dodge Living Artillery simply by stepping outside of the landing spot. But with Rylais, if Kog lands just one artillery, it almost guarantees that the next artilleries will land.
After landing the ult, continue aiming the ult a little ahead of the opponent’s running direction. This forces two decisions: get hit by yet another ult or momentarily stop.
Stopping is no safety. A person who has to momentarily stop has put themselves closer to Kog. If they stop sufficient times, Kog will be able to reliably land an ooze-spittle combo, killing wounded opponents almost instantly.
Kog is not defined so much by “early, mid, late” as many other champs as far as their role is concerned. Rather, Kog’s power and presence is dictated by the rank of Living Artillery.
Before you have your ult, your laning phase should consist of using your spells at maximum range to farm the waves.
- Unless your opponent screws up, you will not win in CS
- Survival is the name of the game
- Don’t bother pushing hard. Autoattacks are like butter slapping a brick.
- If you die, you weren’t playing carefully enough
- Poke to farm
Don't Bother Trading: It doesn’t matter if they’re melee, if they have less range, or even if they’re out of mana. Every spell, every auto should be focused on trying to farm above all else. Your kill potential is fairly nonexistent pre-6. If you think you can kill them by hitting them enough? That's precisely when everything will start going wrong.
Land Incidental Damage: You may not be trying to poke opponents down, but incidental damage is always nice. Try to position yourself to hit both the minion and the opponent at the same time.
Beware the Enemy Jungler: Kog is such an easy target for the jungler to jump on. This is the biggest reason why even poking is fruitless; a competent jungler will take advantage of your vulnerability even if you’re only a quarter of the way down the lane.
Beware Your Own Jungler: Survival is your primary priority. Unless you have a jungler with a mixture of heavy CC and heavy damage, consider informing your jungler to not even gank for you. Kills rarely result unless the jungler has red and you can land a well-timed void ooze. But even this opens up the fight to a countergank that is easy to lose.
Go Back Instead of Pushing: Your pushing power is stupidly weak. Even two uncontested minion waves won’t bring the tower to a quarter health. It’s not worth the risk unless their jungler is in a different lane.
Get a Control Ward Against Flanks: Get an early control ward and set it up to protect from a jungler tower-dive ambush.
Always Improve at Surviving: Every death is preventable. It means you were too far without wards, you were trying to trade, you didn’t dodge enough, or you got surprised by burst damage. Take every death as a learning experience of what to expect for the future and avoid repeating the same mistake.
Use Unsealed Spellbook to Stall Longer: The two best spells to swap to early on Unsealed Spellbook are Clarity and Teleport. The first to stay even longer in lane before recalling, the second to double-dip refill on health + mana or to try countering a roaming foe.
The first rank of the ult is your first major power spike, immediately doubling your power. Upon receiving it, your Barrage Limit starts at 1.
- Prevent opponents from roaming
- Be cautious about roaming; it's often better to refill on mana
- Force squishy targets back with powerful ooze-ult combos
- If you die during laning, you weren’t playing carefully enough.
- Use your basic spells primarily for their utility
- Poke to deter
Ward the Enemy's Half of the Lane: Your opponent will likely have their ult at this point as well and will often begin roaming, as Kog lacks the pushing power to take advantage of their disappearance. Putting wards on their side of the lane will ensure that if they begin roaming, you can warn which direction they go so your team will have heavy advance notice to get away.
Be Careful When Following Roams: You may sometimes want to chase after roaming opponents, but be aware that they may easily be hiding around a corner or in a bush in ambush, waiting to take advantage of your still-weak power. Alert your team, and be extremely cautious of ambushes if you choose to follow them.
Avoid Roaming: It's tempting to roam yourself, but you're usually better off just being more focusing on farming up to Level 11. It may be self-centered, but it's not selfish, because it is the action that maximizes your entire team's chances of winning.
Use Ooze + Ult to Clear Minions: If you use Void Ooze on the caster minions, the execute bonus of the ultimate will proc on them, allowing an instant clear on the minions at later ranks of Void Ooze.
Deter Enemies With Ooze + Ult: Unless your opponent is very squishy, you should largely be using poke as a form of deterrence rather than a form of killing. Still, a successful ooze-ult combo on an opponent can deal substantial damage so always keep an eye out for chances to land one.
Unsealed Spellbook Provides Durability: Good swaps at this point start being Exhaust and Heal, which add even further bulkiness with Kog's ample health and Resolve runes.
You have hit your second major power spike, doubling your power once again. Now that you are 4x more powerful, you may begin poking very offensively at the opponents.
- Keep everything constantly warded
- Clear waves instantly and begin pushing and grouping
- Be wary of dash-combos
- Poke to kill
Keep Mindful the Barrage Limit: Don't go trigger happy with ultimates. While the Barrage Limit is about 2 now, be conscious of how much mana is being depleted. Running out at the wrong time can give the enemy leeway for a tower.
Use Spittle First: Caustic Spittle, Ooze, Ult, Auto. A committing target can’t avoid the Q, which will amplify the damage from the rest of the combo.
Chain Aggressively: Your teamfight presence is now massive even with few items. Rylais will be finished soon and you'll get to start chaining opponents down. Careful however; a wide variety of dash-combos can still reach you even at max range.
Scout With the Ult: Living Artillery grants vision on the location it casts on, so use it to see if the roaming mid-laner is trying to ambush you or if the opponents really are at baron.
Ult Your Feet: During duels against melee targets, keep ult’ing at the ground directly underneath yourself. This will guarantee the hit unless the target decides to disengage momentarily, buying valuable time to make distance.
Aim for the Zhonyas: Whenever you see someone has gone into Zhonya form, keep your eyes extra peeled on them and try to land an easy ult shot rightttt as the Zhonyas duration ends. Once you get good with the timing of your ult, the Zhonyas form is just a free target.
Unsealed Spellbook Provides Options: At this point, the summoners from spellbook will start rotating. Ghost is a good replacement for Flash when it's on cooldown while Smite can be used to help secure an objective, or just to add more CDR onto Spellbook. It's tricky balancing unique spells vs. more useful ones.
This is it. If you have made the game go on this long, another 2x multiplier in power. You are now 8x more powerful and boy does it feel damn good.
- Stay at max range unless an engage happens
- Keep a target locked on and shoot
- Destroy diving opponents
- Poke to win
Caustic Spittle the Tanks: Use your Caustic Spittle to slow down and shred tanks trying to dive into the middle of your team. If combo’d with your spells right after, a few empowered autos is enough to deal insane damage.
Your Dueling is Good: Your dueling potential is extremely strong if you have exhaust from Unsealed Spellbook up. If the fight is starting to die down, consider getting closer to the fight and pick off the remaining opponents with your Bio-arcane autos, which now do fairly hefty damage in their own right.
Flash + Ult: Opponents will often try to break your chaining by flashing out of it. Flash toward them to immediately close the gap and continue chaining. Also use to get the last bit of distance to snipe a flee’ing opponent, but be wary that if they’re not CC’d, they can dodge the ult and waste your flash.
Use the Nexus Regen for Last Stands: In dire situations where you have to hold off several opponents from the nexus turrets, you are able to stand at the edge of the base regeneration and unleash a literally endless stream of bullets. This allows you to become the absolute final line of defense when things are looking grim.
Chain a Backline Target: You can safely pick targets every fight who you want to hunt down and chain them to death. Often, just a 3 or 4 artillery chain is enough to send an opposing magician to a quarter health or less for one final execution shot. Pick a target and keep them locked on.
Making Good Impressions
The Barrage Limit has been mentioned several times in this guide, so now is the time to learn how to increase it.
Keep note that the Barrage Limit is not an upper limit on how many times you should shoot in a fight, but a general guide on how to maximize your consistent damage. As you play Kog more, the Barrage Limit starts to become more instinctual.
Barrage Limit starts at 1 (because of Tear) and increases depending:
Raj of Barrage
There are times when it's time to stop holding back and go past the barrage limit. Blow out a full 10-ult barrage and cripple opponents... and yourself.
Realize that pushing past the barrage limit too much will make you useless for any further fighting. As such, it makes sense that the barrage limit should only be exceeded when something can be secured or defended.
That can mean a several things including but not limited to:
- Securing a kill
- Securing an objective
- Securing a kill to secure an objective
- Defending a turret from low-health opponents
- Keeping a small area scouted while taking a ward
- Taking blue buff quickly, since the mana will regenerate
- Holding off opponents from defending an objective when it is almost dead
- Stopping a baron/dragon attempt; remember that baron shreds magic resist!
- Rushing a baron/dragon where your team plans to peace out after securing it