Karthus Build Guide by Insightful
[S11 Challenger EUW] Rank 1 Karthus world | In-depth guide oBy Insightful | Updated on March 2, 2021
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+9 Adaptive (5.4 AD or 9 AP)
+9 Adaptive (5.4 AD or 9 AP)
Ability Order Skill order
Threats & Synergies
Nunu & Willump
Champion Build Guide
- It has the fastest clear speed of the jungle monsters
- Very healthy clear
- Huge amount of dps throughout all stages of the game
- Global pressure
- Strong duelist
- Fits in pretty much any team composition
- Strong sidelaner
- Scales really well
- Immobile champion
- His DPS is very reliable on skill shots
- You need to practise his clears in order to optimize them
- Weak vs high ranged compositions
- Weak vs invade junglers
There's no secret when it comes to summoner spells, you always use flash and you want the blue smite.
Despite karthus being a very good duelist and there's definitely a scenario where you could go red smite, the blue one is more effective, because it grants you a slow on your enemy which makes it easier to land Qs, and for them to stand in the range of your E, so they can't get away from you.
This rune is literally designed for karthus, it has the perfect synergy for a champ with AoE spells, constant DPS and an ulti that can easily proc it.
Out of all the 3 this one is the best for junglers, karthus doesn't have any mobility so sudden impact doesn't do anything on him, and since you're not laning against anyone, taste of blood won't do any healing until you find people on the map, so Cheap shot is the best choice to give you extra damage in combat and when you're going to gank.
It's not really your job to clear vision on karthus since you're a squishy immobile mage, so the other 2 runes don't make a lot of sense to him because you never go sweepers.
This is where most people would have their doubts, because as we know, karthus ulti cooldown is the longest in the game and it has a huge impact in fights aswell, however the reason why you use this one is because it will allow you to always be full HP while clearing jungle camps, and provide you with a bit of sustain in fights which can be crucial to win them. Usually if your ulti is not up, you don't want to force anything unnecessary, playing around karthus ultimate is something that eventually you'll learn to do with the more you play the champion.
Karthus is a very mana hungry champion, and since the item rework, a lot of champions have found issues with their mana pools, this is the rune you take to make sure you mitigate this problem in fights.
Now this is the rune that truly makes karthus shine, Dark Harvest is good, but this rune can often outperform it by a simple reason. The lower HP you are, the more damage you deal, what most people don't know is, that when karthus dies it counts as if he had 0 hp, so you're basically making use of 100% of this rune, it's a must take on karthus to increase your damage and it's heavily underrated because a lot of people could argue that coup de grace has more value to your ultimate, however, after 1 million mastery points on this champion, I can guarantee you that last stand outperforms in every single game.
Karthus can use all of the mythic items to be honest, but after testing a lot, Liandry's Anguish is by far the best choice, karthus has a huge amount of dps and damage over time with his E and passive, which means that it can make full use of liandries magic penetration and keep applying it's burn.
Zhonyas is just an item that has perfect synergy with his kit, you can press E and zhonyas and the enemies will be stuck on your range recieving damage for every second they're in it, it's very strong against teams with a lot of champions who want to dive the backline and melee champions in general.
You always go sorcerer shoes on karthus for a very simple reason, you don't need defensive boots because even if you die, you're still going to stay in combat, so these are the boots that will amplify your damage the most regardless of the situation.
Dark seal is a very cheap and cost efficient item, specially if you manage to get it stacked, even if you die on karthus and still press ulti, you can get a few stacks on it, which is why it's very good on it. You should try to buy it every game and if the game is looking good, maybe upgrade it to a mejais.
If you want a bit extra tankyness and damage over time, if you're dealing with teams who have a lot of melee champs and a lot of mobility, you want this item to make sure you can survive longer in fights and that you can do as much damage over time as possible.
Rylais is a bit similar to demonic embrace, however the biggest difference is that even thou it gives you more ap, the damage overall is lower the longer fights last, so this item is more of utility, you can buy it if you want to peel your backline by perma slowing enemies, or if you simply don't want them to get out of your range, it's very good vs champs who have a lot of movement speed buffs.
Well, I put this item on situational but it's probably a must buy on every game, it depends a lot on how the game progresses, sometimes you're going to be so far ahead, that the magical penetration you get from liandries is enough, however if the whole enemy team starts buy 1-2 MR items, you want to get a void staff.
Mejais can be very good in most games, if you're able to get dark seal to 10 stacks, always get mejais, even if you die on karthus, you can just press R and if your team wins the fight you might get all your stacks back or even more, this is an amazing item to snowball the early/mid game if you're ahead, always consider buying it.
Deathcap is the AP item that will by far give you the best stats, however, it is quite expensive and it's componnents aswell, which is why you have to read the game to know when to buy it.
It's only a core item for you, if the enemy team is basically full squishy or high ranged champions like marksmen and mages, games where it's hard for you to get into their range, so it's easier to just get as much AP as possible and press R.
Morello is a healing reduction item, sometimes the enemy team will have a lot of champions with healing abilities and that's when you should take it, out of all the situational items, this is the one you'll use the least probably. Only buy it if you think the enemy healing is actually a problem to you.
Karthus' passive is in my opinion what makes him such a strong champion, the fact that even if you die you're still able to stay in combat grants him a huge advantage over other champions in a fight, because it mitigates the impact that your mistakes have, and it can be used in many ways, you can use it to zone the enemies from walking past you or to intentionally die to cast your ulti uninterrupted. It allows for a lot of strategical options, since with karthus, sometimes dying might be the better option for your team!
This is your main ability on the champion, it's the one you want to max first, and the main source of your DPS. It's not an easy skill to land because it has a small delay, but once you practise enough, it becomes very satisfying to play.
His W is a very simple point and click skill, the best use of it is to slow down enemies to make sure they can't run away from you, and to make it easier to land Qs.
Keep in mind this skill also gives you % magic penetration! which has great synergy with liandries. However, this skill is not so important in comparison with others, so I recommend it for you to max it last.
His E can be very tricky to use, if you always leave it on, you'll run out of mana really fast, so you only want to use it when your oponnents are in it's range, always try to focus on landing Qs, if you rely too much on E, you'll find yourself in a position where you're not doing damage and you're out of mana. It's a hard skill to get used to early in my opinion, but the more you play the champion, the better your mana management becomes and you can use his kit more efficiently. This is the skill you max after the Q.
Well, if anyone made a poll on what's the most frustrating ultimate of league legends, Requiem would for sure be the rank 1. The highest cooldown skill in league and by far the most hated. Point and click damage to all 5 champions of the enemy team after a 3 seconds cast. Usually you want to use this ability when the enemies are low hp to finish them off, but sometimes you'll want to use it early before a baron fight starts to make sure that oponnents can't contest it, it's up to you to read the situation. This is karthus' most valuable skill for a fight, reading the situation and when to use it can be crucial to the outcome of a fight, but like the rest of his kit, you have to get experience to improve your judgement on when to use it.
As shown previously, this is how you should skill your abilities. You max Q for damage, then E, then W.
The only secret here is that when you play jungle, you don't skill your W level 3 because it does no damage to monsters or creeps, so if you put 2 points on Q at level 3, you're basically able to clear the jungle faster.
Level 5 Threats:
The champions who are in this category they all share the same characteristic, basically, they can beat you at any stage of the game, you won't win early and you will not outscale.
The reason why they're impossible to win matchups it's because the higher you climb, the more likely you are to just be level 2 invaded inside your own jungle and die, and there's not a lot of coutnerplay to it, besides warding the map, you should not play karthus into these champions and if possible, always ban one of them.
Always try to play on the opposite side of the map, and never try to 1v1, you can try to 2v2 or 3v3 if your teammates have enough cc to lock them down, they all have mobility and can easily dodge your Qs and they have burst damage which means if they get ahead they just 1 shot you, and the worst part is, they can also keep up with your jungle pace, they can powerfarm as well as you do, so there's no hope in these matchups besides hoping they're really bad or your team is really good.
Level 4 Threats:
The difference between the level 5 and level 4 threats is basically on their power curves, These champions unlike the previous ones, you're able to defeat them early on, but you do not outscale them, if they get ahead early they just snowball on you. However it's not as punishing because they're not really focused on invading and destroying the enemy jungle.
The biggest counterplay you have in these matchups is to try to harass them early on by invading and stealing their jungle camps, since you should always be ahead in tempo due to your faster clear speed
The nunu matchup is a special case, because this champion win games by ganking a lot early game, while mantaining a good jungle clear. fighting him doesn't do anything either, because not only is he a tank but he also runs phase rush which makes it pretty much impossible to kill 1v1. By the time you show up strong to play the game, the nunu could've already ended by ganking your laners. Eventually later on you outscale him and you can have more impact on fights than he does, so try to tell your laners to play safe and scale up.
Level 3 Threats:
I would say the level 3 threats are pretty even with karthus, but at the same time, they have a small disadvantage that every other champion shares, which is a slower jungle place. These matchups can be easily won simply by farming your camps and scaling up, however, those champions have their tools to try to keep up in farm and while not being as efficient as karthus is, if they do pick up an early lead, they're able to snowball on you, which is why I think these matchups are even.
I would still say karthus has a small advantage, it's just important not to make mistakes in them to avoid being one shotted later on.
Level 2 Threats:
All the champions in this category are just bad at dealing with karthus, it's very hard for them to keep up with your jungle clear speed, and try to fight you early on. The only way you fall behind here is if they get a huge lead, even a small one isn't enough to make you lose, you should always be able to stay ahead in these matchups.
Level 1 Threats:
These are matchups you instalock karthus against, there's nothing those champions can do to be honest, it should be a free win.
Perfect Synergies Toplane:
What you want from a toplaner on karthus ideally is an AD champion, who can setup ganks/dives and later on can go sidelane but at the same time, be very impactful on teamfighting to be able to get to the enemy backline.
Karthus works very well with champions this, because imagine a riven in a teamfight trying to kill through the enemy backline, if she has a karthus ulti that takes away 50% of the carries' hp, her job becomes a lot easier, but it also helps if she's on sidelane 1v1 with the enemy toplane you can use your ulti to help them win their matchup.
I know a lot of the champs that I put on a level 4 of synergy fit this description, but from my point of view, only partially, since they can't both teamfight and be impactful on sidelane as good as these champions.
Perfect Synergies Midlane:
Midlane it's pretty much the same as toplane, the difference is you want your midlaner not only to be able to do everything that I mentioned above, but also to have a lot of lane pressure to make sure that the enemy jungler cannot invade you.
The perfect example for this is Nocturne.
However I still put zed and qiyana very highly rated due to their ability to impact the game, they're not as lane dominant as nocturne is, but once you scale up a bit early on, it's very hard to lose fights with these champions and later on aswell.
Perfect Synergies ADCs:
The reason why I don't have any adcs at this rating is because as a jungler, adc is basically the lane you interact with the least, I put senna and ashe as the 2 best adcs for karthus, but for the sake of the rating system, I cannot say they're as useful as the champions in this list are.
Perfect Synergies Supports:
I want to seperate the supports into 3 categories, the first one is nautilus and leona.
As I said earlier, karthus's kit fits pretty much into any team comp, and if you have hard engage, these 2 are the ones you want on it.
They have plenty of crowd control to keep the enemies CC locked and unable to move, making it very easy for you to land your skillshots and kill enemies.
Karhus is also a very high dps champion, and like every champion with a lot of damage, having a support that can enable your kit is always helpful, while nami is a more agressive support for karthus, as in, she's better if you want to do more damage and lock your oponnents in bubble or her ulti, Janna is a better defensive option and ofters better peel or disengage, nonetheless, both have an amazing synergy with the champion.
The broken synergy:
This will sound a bit weird at first, but soraka is by far the best champion to have on your team as karthus.
Her global ulti compliments yours, basically you setup your team to never lose sidelanes and to have 2 globals for teamfights, adding a lot of pressure to the oponnent.
Soraka is the only champion who is really good on EVERY lane with karthus jungle, if she's solo lane you can easily funnel her and then take sidelane waves, if she's bot or supp she can ofter you a lot of sustain/peel.
You can't go wrong with a soraka on your team.
The others follow the same process thinking as everything that I mentioned above, however, they're not as good from my personal experience, or as efficient as they are with these particular champions.
Now that you know the spells, runes, items,which champs are good against/with karthus and which abilities you'll skill it's time to teach you how to actually jungle on this champion.
The jungle clear on this champion is it's most powerful tool, to do it 100% efficiently you're gonna have to kite jungle monsters.
But it's more than just spam your abilities on the camps, to be 100% efficient, you must always use 2 Qs and 1 auto, repeat this pattern always in order to clear it as fast as possible.
You always start on blue side and you always full clear, ALWAYS.
This takes a bit of practise to achieve, so go to practise tool and if you're commited to it, feel free to check my vods on twitch aswell if you need to see it being done.
You have optimized your clear once you achieve full clear in less than 3 minutes with leash.
It's very important that when you play a champion you understand what will make it win, luckily karhus has quite a few.
The most important one is to play around objectives, such as drakes/baron.
Due to his high dps nature, he can bring down objectives really fast in comparison to most champions which really enables your team to simply just rush them if the enemy team is lurking around the map. Fighting in closed locations is also very good since you have AoE damage and can hit multiple oponnents in fights.
The second win condition would be to play for sidelanes with your ultimate, or you can do it yourself aswell, karthus is a good duelist, obviously he's far from being the best, but he can handle himself vs a couple of champions specially if he's ahead.
If you find it hard to coordinate with your team to play sidelanes, which sometimes can be very frustrating in soloq due to the lack of communication, just group and fight it out, in the end, it's what karthus does best :)
Thank you for reading up this far, I'm sorry if the guide lacks a lot of visual effects to demonstrate my views a bit better, but hopefully in the future I'll be able to improve it a bit more.
Feel free to drop by my channel if you have any other questions, I'll be happy to answer them.