Mobafire League of Legends Build Guides Mobafire League of Legends Build Guides

Karthus Build Guide by Mikuroo

This build has been archived and is for historical display only.

PLEASE NOTE: This build has been archived by the author. They are no longer supporting nor updating this build and it may have become outdated. As such, voting and commenting have been disabled and it no longer appears in regular search results.

Not Updated For Current Season

This guide has not yet been updated for the current season. Please keep this in mind while reading. You can see the most recently updated guides on the browse guides page.

Like Build on Facebook Tweet This Build Share This Build on Reddit
League of Legends Build Guide Author Mikuroo

Karthus - Repeat Sign of Death [In-Depth] ~ Competitive Play

Mikuroo Last updated on May 20, 2012
Did this guide help you? If so please give them a vote or leave a comment. You can even win prizes by doing so!

You must be logged in to comment. Please login or register.

I liked this Guide
I didn't like this Guide
Commenting is required to vote!

Thank You!

Your votes and comments encourage our guide authors to continue
creating helpful guides for the League of Legends community.

LeagueSpy Logo
Middle Lane
Ranked #13 in
Middle Lane
Win 50%
Get More Stats

Ability Sequence

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

Not Updated For Current Season

The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.



Offense: 21

Honor Guard

Defense: 0

Strength of Spirit

Utility: 9

Guide Top


hello, this is Mikuroo with his guide to playing Karthus on Summoner's Rift! Please note that you do not have to follow everything exactly, and that this guide is to help you along. I hope this guide will fit many peoples needs! PLEASE READ ALL OF IT BEFORE VOTING. I WOULD REALLY APPRECIATE IT!.

This guide works well with really any team, and should be used when your jungler really needs blue buff to farm properly, because Karthus does not need blue buff. His Defile gives him back enough mana from last hitting.

However, Karthus does need a jungler with strong ganks, because karthus alone cannot really go for the kill, but harass with his Q once and a while .

Karthus is a underrated champion that I do not see nowadays too much. However, he is a very good champion that most people call a "noob champion" or a "Press R, GG". However, if you ever play or try karthus, you will realize this is wrong.

Well, onto the guide! Enjoy!

Credits to jhoijhoi for the template, which you can find here.

Guide Top

Pros / Cons

Pros / Cons
+ // He has a global ultimate
+ // He has really good farming ability
+ // After dying, he is still useful
in a team fight.
+ // He does great sustained damage
+ //does not need blue buff
+ // He has a great 80% slow, also
increasing his teams damage.

- // Not enough burst in comparison
to champions like Brand
- // Must be very well farmed.
- // Global Ulti can be countered
- // Very Squishy, and if passive is
not ultilized, you will be useless.

Guide Top



I go 21/0/9 for many reasons. I believe that late game karthus is a beast, and the last masteries in the offense tree are therefore a must. Executioner is a must on karthus too, because every time you use Requiem, your target should be below 40% health.

The points in the utility tree are obvious for an AP Carry, and the mana regen is needed if you are not going to take blue buff. Wait, if I'm not getting blue buff from my jungler, why do I need Runic Affinity ? because late game you will need blue buff, and your jungler will not. You will only be giving it to him early game to raise his clearing speed.

Overall these masteries are quite self explanatory. However, I feel I have to explain why I do not go 21 points in utility like many other Karthus' do. I feel if you are going AP carry with karthus, you really need all the AP Help you can get. What are the points in Utility going to do for you? Close to nothing! Karthus is a really underrated AP Carry, and when well farmed he does amazing damage.

Guide Top



Greater Mark of Magic Penetration

Greater Seal of Mana Regeneration

Greater Glyph of Scaling Magic Resist

Greater Quintessence of Ability Power
  • : The 15 extra AP is almost needed on every AP Carry in the game I think. I cannot think of any quintessence I would take otherwise.
  • : Magic penetration. It increases your early game damage, so you can carry yourself into the late game.
  • : So that you don't get demolished by Ap Carries. This is quite unimportant however, and you may replace these glyphs if you want. I really will not mind.
    : Some people use this, but I find that that little bit of magic resist goes a long way. Your choice.
  • greater seal of replenishment: We need mana regen to sustain. I do not however, take mana per level, because I will have enough mana late game, and I will be taking blue buff late game. These are good, because early game with Defile passive, Tear of the Goddess, I will never run out of mana, and I will still be able to harass with Lay Waste.
    : the reason I do not use these is stated above.
    greater seal of vitality: These are the runes someone suggested to me, and I do believe that they would work, however, I believe that Karthus needs mana regen. Why? you ask me. doesn't Defile give all your mana back? Yes, it gives some, but since Lay Waste will always be at a higher level then Defile, it will be giving back less mana then a Lay Waste. Still, these are great.

Guide Top

Summoner Spells

[Flash]: This spell is almost needed I think on Karthus. This is because your only escape method is Wall of Pain. Early game, this is horrible, and you need escape routes. Also, this can be used to position yourself for a death so that you can abuse Death Defied.

This spell gives you that extra power when your Requiem just won't cut it. I know most mid karthus' take Teleport, but since I have tear of the goddess and rod of ages, I certainly don't need it. So this is the next best spell. It is also good at first blood, an people with insane healing (skills like Sadism, or just lifesteal).

[Teleport]: I really believe this is needed on karthus. It gives him so much sustain, that all he needs to go back for his HP. If you dodge skillshots, this is not a problem. Also, late game Karthus is quite a good pusher with Defile.

Guide Top

Ability Explanation

Ability Explanation
Many people on Karthus will max Lay Waste, then Defile, then Wall of Pain and max Requiem whenever possible. I however, disagree with some of this.

You should max Requiem whenever possible

however, the rest of the skills are optional. You really do not have to max Lay Waste, but it is most recommended. your skill order should be based on your jungler, and what level of Wall of Pain you need to secure kills. a 40% slow is so much worse then a maxed 80% slow, and the resistance drops are enormous.

most games, you should max Requiem whenever, Lay Waste first, then Defile, then Wall of Pain. BUT THIS IS NOT WRITTEN IN STONE. IF YOU FEEL YOUR JUNGLER IS NOT GETTING OFF GOOD GANKS, POP A POINT INTO WALL OF PAIN

Below are my in depth explanations of the skills that are needed and used on Karthus, and several tips on each of how to use the skill. I spent most of my time in this part, so I hope you enjoy!!!

Guide Top

If they have a strong jungler

If they have a strong jungler, simply take wall of pain at level 2, and defile at level 3. Then continue to max out Lay Waste, putting points into Wall of Pain ONLY WHEN NEEDED. Of course, always max out Requiem.

Guide Top

Each Skill - TL;DR

If you really don't want to read my essay about each skill, it doesn't really matter to me, but I still think I should summarize each skill for you and tell you the important parts that you need to know during the game. So here are the brief skill summaries:
  • – This skill allows you to live after death for 7 seconds.
  • – Use this skill to harass and last hit minions. Abuse it’s short cooldown.
  • – Your slow, killing tool, escaping tool, it has a very large range.
  • – Early game, you use this for the mana, leave it toggled off. Late game, toggle it on for great aoe damage.
  • – This is your signature move. KS some peeps, get fed, win games.
    And those are Karthus’s moves bottled up in a sentence or two each! If you really want to read my in depth essay version of each, be my guest. I didn’t write them for nothing…

Guide Top

Death Defied

(Innate): Upon dying, Karthus enters a spirit form, which allows him to continue casting spells for 7 seconds. During this time, his abilities cost no mana

This passive is in my opinion is what makes Karthus good. All Ap Carries have to be squishy in order to deal enough damage, but this is what lets karthus go almost full AP without losing too much damage output. As the other team focuses you first, you get to keep dealing damage for 7 seconds, and allows you to cast your ultimate without interference. REMEMBER, YOU WILL BE STUCK ON ONE SPOT
  • Sometimes in a team fight, you have to die for your team to win. Make sure to die in the middle so that your Defile deals its maximum damage, and use Wall of Pain to keep enemies in range. Spam Lay Waste for damage output, and if your team needs it, cast Requiem before the 3 seconds ends.
  • If you bait your opponent into killing you first, you team will have the advantage because they used abilities on you, and your team can now demolish the other team without worrying about stuns, snares or slows. You can continue dealing damage.
  • Sometimes it is smart to die so that you can use Requiem. It is risky to use requiem while alive because if you die, it is wasted , and by wasting this skill, your team is put at a huge disadvantage.

Guide Top

Lay Waste

(Active): Creates a delayed blast at the cursor position. After a half a second delay, it will deal magic damage to each nearby enemy. The damage is doubled if it hits only a single unit.

Cooldown: 1 second
Range to Center of AoE: 875
Radius of AoE: 100
Cost: 20 / 26 / 32 / 38 / 44 mana

Magic Damage (Multiple Target): 40 / 60 / 80 / 100 / 120 (+0.3 per ability power)
Magic Damage (Single Target): 80 / 120 / 160 / 200 / 240 (+0.6 per ability power)
  • This skill is your main farming tool. Karthus can farm with Lay Waste because of the mana return from Defile. This is convenient because his auto attack animation is not very great. However, because of the insanely low mana cost, you can use this to charge your Tear of the Goddess, and poke every couple of seconds.
  • This skill does double damage if it only hits one target. Use this when last hitting minions. But also remember that it has a small explode radius. If you put this on top of a minion, it will probably hit other minions, which risks not getting the last hit, and also pushing the lane. When you last hit, place the mine slightly away from the minion. Below is an example of this.

  • You can hide this skill under minions or champions so that it hits. It is actually not very noticeable, and if you catch your enemy not paying attention to the ground, you will get easy harass. Try to find out which direction they will walk in and play mind games. [/color]THIS SKILL DOES SOOO MUCH DAMAGE WHEN IT HITS, ABUSE ITS 1 SECOND COOLDOWN

  • If you cannot hit this spell, honestly, you will not be able to play Karthus. This is your main damage output, if you cannot predict your opponents path to hit this, you will be useless.
  • You also have to remember that this skill gives sight. It is an excellent face check, for little to no mana, and an 1 second cooldown. This will allow you to never walk straight into a bush ambush, as long as you are aware and check bushes with this skill

Landing This Skill
  • The most important part of this skill is really how to land it and deal the maximum damage, abusing its one second cooldown. Below I will show you some tricks and tips on landing this spell in a real game, to abuse Karthus' strengths.
  • Know the enemy champion, the playstyle of who you are laning against. Remember, if you lose your lane, then the other teams mid will be fed, and will start winning them the game. And worst of all, it will be your fault.
  • So how do I find this out? See how he dodges your Lay Waste, and this is where mind games begin. Your opponent WILL NOT continue a same pattern for the rest of your game. BUT YOU HAVE TO CONTINUE LANDING YOUR Lay Waste'S. It may be hard, but remember, its on an one second cooldown!
  • The easiest time I find to hit my Lay Waste is either when the opponent is trying to last hit, or he is trying to harass me. Their movements are much more easily predictable, and lead to easy hits. If they are moving so that they can hit you with a skill shot, but you are behind creeps and they need a better angle, put your Lay Waste where you think they are going, and chances are you will hit.

Guide Top

Wall of Pain

(Active): Karthus creates a wall between 2 obelisks at target position. Any enemy passing this wall have their armor, magic resistance, and movement speed reduced for 5 seconds. The wall lasts 5 seconds.

Cost: 100 mana
Cooldown: 18 seconds
Range to Center of Wall: 1000
Wall Length: 800 / 900 / 1000 / 1100 / 1200
Maximum Wall Sight est.: 1300 / 1325 / 1350 / 1375 / 1400

Armor and Magic Resist Reduction: 15 / 20 / 25 / 30 / 35

Slow: 40 / 50 / 60 / 70 / 80%
  • This skill is your only form of cc. However, it is a very good spell. At max level, it slows by a massive 80% for 5 seconds, and it has a huge range, not to mention 35 armor and magic resistance. This spell allows for your team to pick off stranglers very easily when positioned correctly.
  • After dying, use this skill in combination with Death Defied so that you can keep enemy champions in your range for Lay Waste. If you die and you cannot deal any more damage, that is a wasted passive, and a huge disadvantage to your team.
  • You do not always have to put this horizontally, in case you miss your opponent, or you place it in front of them and they just Flash over. Either put it on top of your opponent exactly, or put it in a straight line that your opponents are walking on.
  • Do not forget that when you are running away, this skill can block almost every pathway in the game, if not all. Use this wisely, it could mean the death or life of your teammates, maybe even the fate of the game. NO PRESSURE.

Guide Top


(Toggle) - Off: When Karthus kills a unit, he restores mana.
On: Drains mana to deal magic damage to nearby enemies each second.

Mana Restored: 20 / 27 / 34 / 41 / 48 per kill
Radius of AoE: 550
Cost: 30 / 42 / 54 / 66 / 78 mana per second
Magic Damage: 30 / 50 / 70 / 90 / 110 (+0.25 per ability power)
  • This skill is amazing, and every AP caster in the game wished they had this skill. Except for Kennen. He can go die. and anyone else that doesn't use mana. Anyways, this skill allows for sustained early game, and damage late game. You will have it toggled off during the laning phase, for the passive mana regen from last hitting. You will have it on when attacking opponents, and you won't run out of mana quickly because by now, you will have alot of mana.
  • There really is nothing more to this skill. It is really simple, I mean, mana regen, and insane aoe damage. However, one thing that should be pointed out is that during a team fight, this should always be [/color]ON If you turn it off, you lose damage. Simple as that. Keep it ON while you are dead also.

Guide Top


(Active): After channeling for 3 seconds , Karthus deals damage to all enemy champions.Cost: 150 / 175 / 200 mana
Cooldown: 180 / 150 / 120 seconds
Magic Damage: 250 / 400 / 550 (+0.6 per Ability Power)
Range: Global

  • When people think of Karthus, they think of this skill. This is what makes everyone assume karthus takes no skill. However, there is alot of responsibilities and skills that go along with having this global ultimate. Do not, ever in your life, over estimate this skill. EVER. It will make your attempts at using this fail.

  • Only use this skill when you are sure you can get a kill. If you miss a kill, I assure you a minute later, when it is on cooldown you will be like "DAMMIT IF ONLY I HAD MY ULTIMATE!" This skill allows you to get fed without beating your laning enemy champion. This also means, do not use this skill on people that have a spell shield, unless it is on cooldown, like Sivir, Nocturne, or a skilled Shaco that can time his deceive perfectly. The list goes on, this skill as you can see, is not that overpowered and can be countered easily. TIMING IS EVERYTHING ALWAYS SEE IF YOUR OPPONENTS HAVE Heal!
  • Every time you buy an item, re check how much damage this ability does. Most of the time you are going for a kill, you should remember this number to make sure the opponent will die. This is fairly difficult later game, as you will have to judge magic resistance and magic penetration. ON THE SPOT. Get used to it, ALWAYS KNOW HOW MUCH DAMAGE THIS DOES. You miss that kill by 30 hp? Poor baby, you can whine all you want and say LUCKY WOW QQ all you want in “all chat,” but you can only blame your judgement.
Landing this Skill:
  • I know what you may be thinking right now. This skill has a 100% hit rate, why are you writing this? I am talking about landing this skill successfully. In order to get fed, you actually have to get kills with this and pick off what your teammates couldn’t get. What does this mean?
  • This means map awareness, and watching constantly on your map for chances. Better yet, if you are playing a solo/duo or a premade 5vs5, have you team yell out when to ulti. By having good communication, you can get easy kills with this. By telling your team also right before you are using Requiem, they can go and try to set you up with a double, or possibly triple kill.
  • Never. Ever. Use this in lane. Use it under a turret, or safely inside a bush where enemies are not near.Why? Because you would not believe how easy it is to interrupt this ability. Silence, stun, Impale, basically anything will make you Q_Q and waste your ultimate, waiting another gabillion seconds before it gets off cooldown. Okay, so now you understand that, you also have to understand that you won’t always have that precious time to walk under your turret and cast Requiem. Remember, your team may get a sudden near kill, and if you weren’t positioned correctly to cast Requiem you may have lost a kill. Abilities like Wish may counter your ultimate, but not if you had casted Requiem a few seconds ago. THINK.

Guide Top

Laning Phase


You should buy wards whenever you think you need them. Do not blame your team for not calling mia's or your jungler/support for not warding. It is really you who benefits most from wards, because if your lane opponent gains advantage, you are going to be zoned and this will generally lead to a ****py game.

However, this does not mean stack up on sight ward, because you need your core items too. Learn when and where to ward, if you ward the bottom river, you do not need to ward top river if you stay closer to the bottom river. Wasting money is Lowering your power.

Last Hitting

You should be last hitting with Lay Waste, and focus on that. Remember, do not play Karthus as a burst character like Kennen. You have to play conservatively, do not worry, you will get late game to get kills. Also mentioned above, by playing passively, no one in middle lane will get kills. Except you. With Requiem. Passively harass with Lay Waste, and if the moment really shows itself, go for the kill. However, do not use Flash to get kills, you need it for when the enemy team pulls off a good gank.

Karthus is good at pushing his lane, but I would advise against it. Push as much as the opponent is pushing so as to not lose farm to your turret, but do not push. IF the opponent pushes, all you have to do is spam Lay Waste, you do not even need Defile on because Lay Waste pushes soooo hard.

Read the section about Lay Waste on how to last hit more effectively.

Fighting is really the most important part of the game. As Karthus, you want to place Lay Waste off cooldown, but keep Wall of Pain up whenever, because it disrupts, and lowers resistances. Keep Defile up whenever, you should have enough mana to.

DO NOT EVER REQUIEM IN A TEAM FIGHT WHILE ALIVE, UNLESS YOU CAN GET A PENTA-KILL. If you start a requiem for one kill, and they kill you, then you just lost that kill. You could've waited for death and then requiemed, and your team would be much better off.

Check out each section for each of the skills to learn how to use them best in a team fight, or maybe just a 1vs1 fight.


Karthus' Passive is amazing and one of the best passives' in the game for team fights. Read the section called Death Defied for more information on positioning this skill and using it to your advantage to the best extent.

Ok, so I know Baron Nashnor isn't during the laning phase, but he is kind of similar to dragon, in the way that they are both super important neutral monsters.

One of karthus' advantages on taking these important monsters is that his damage goes through the roof. This Is because Karthus' damage is broken 1vs1 against a stationary target. AND WHAT DO WE KNOW THAT'S STATIONARY? you got it! Dragon and Baron!

Why is karthus' damage broken? Lay Waste. It's single target damage is really amazing, add it's 1 second cooldown, then take the constant aoe damage of Defile, then take the magic penetration of Wall of Pain. These abilities combined allow your team to take baron or dragon earlier then usual, so take advantage of these.

Guide Top

Team Fights

During a team fight you have several decisions:
1. Your team has a good position and advantage over the other team. Stand back, slow the enemies with Wall of Pain, try to hit the carries so they die faster. Keep defile on, but stand back and keep using Lay Waste. Only when all of the other team is running away may you use Requiem. Do not risk getting your ultimate cancelled by a stun/silence.

2. It looks pretty even. This may sound funny, but find a good place to die. Maximize your damage output from this location, using all your abilities as you normally would. NOTE: Do not walk into battle and die in 2 seconds, your long term goal is to die. Do enough damage and make their team waste cc on you first. If you are planning to use Requiem, use it before the last 3 seconds of Death Defied.

3. Your team is going to lose. Run away, for heavens sake your the AP Carry, you are worth more gold. Do not forget to Wall of Pain. Also, if the enemies are far enough from you, you may kite them with Lay Waste.

Guide Top


These are my item choices, Feel free to change them to suit your own needs. However, I find that these items are the most efficient, But work best with a GOOD TEAM, AND COOPERATION SKILLS. I will explain my choices for each item below, add some optional items, and explain why I do add some of those optional choices in my main build.

  • Boots are required early as an AP mid to dodge all those skill shows that most champions have. These plus the 3 health pots give you great sustain. Karthus really has no sustain, so these help early game when you are still trying to figure out your opponents playstyle. Mistakes happen!

  • I consider this a core item, as on most AP Carries. mercury’s treads are not even viable, and do not even say anything about Ionian Boots of Lucidity, If you think your Lay Waste needs a lower cooldown, then you’re wrong.
  • I rush rod of ages because it gives me the early game sustain, and rushing it is better for the stacking of the item. I am not saying you should always buy this first, it is just a lot better when done so. This item gives good mana and health, and a nice chunk of ability power, and I consider it a core item.
  • This is a must on all AP Casters, most of the times. It maximizes ability power, which is what you need during this part of the game. There is really not much else to say, this is so cost efficient and gives so much for so litte.
  • This item is in my build because of the crazy sustain it gives. Early game, you may not have to recall for quite a while. Also, late game this will give you a bit more time to deal your damage, with your Defile and Lay Waste. Also, Zhonya's Hourglass will give you a heal effect.
  • After experimenting with builds, I put this in my main build. However, I do not think this item is superb or anything really, it is just that there are no really good other choices. Many people say this makes Karthus a good initiator, and it is kind of true. Still, this item is really good. Remember, Defile still works will this is active.

That is my main build that I usually use. Next are the items that we could use, or that I just couldn't fit into my build. If you do not agree with my reasons, feel free to tell me, In fact, I invite you to!
  • Sometimes you just don't even need this item because of all your magic penetration. Your Wall of Pain, plus your runes, plus your masteries. Buy this after Archangel's Staff only if the opponent has quite alot of magic resist.
  • I get this second because I need to give it time to charge up by the time I buy Archangel's Staff. This is also great because it increases the amount of poking you can dish out. I believe Tear of the Goddess is a must on karthus, to abuse his 1 second cooldown on Lay Waste.
  • This should be quite nicely charged up by the time you buy it, and boosts your Ability power by a lot. I used to have this is my guide, however, it was pointed out that Rod of Ages and Teleport was enough mana sustain.
  • This is a great item on karthus because it allows for extreme kiting and chasing. By hitting your first Lay Waste, you can then proceed to kite a person forever! If you are having troubles landing one, no proble, lay down Wall of Pain first. This also gives karthus the Health he needs early game to not be squishy.
  • These items are nice items that will give you the survivability. I would buy these items if your team is kind of sketchy, and you cannot trust them to finish off the enemy team after you have truly died. (after Death Defied duration). However, I do not normally build these.
  • This item is actually good on all casters that get alot of ability power, however, I do not get it because it cannot be casted while a "ghost" in Death Defied ( I think, correct me if I'm wrong). If the other team is pretty tank, feel free to get this, and buy kage's lucky pick early, right after Tear of the Goddess. Build this as your last item, or second last.
  • This is possibly the worst item to get on karthus, and many people who have not really played karthus would think it is so good. Sure, you can stack so many kills by Requiem, but in a team fight, your goal is realyl to take focus, die, and deal more damage. Then lose 1/3 of your stacks? Have fun with that.But if you feel really confident in your team, LIKE REALLY CONFIDENT, you can buy it. Why? because after death, you will receive 4-5 stacks from assists anyways. Of course, only if your team is competent and picks off all the kills.
  • This item is very good against AP Carries, and also gives you good health and mana. If you want to put this into your build, I would suggest taking out Zhonya's Hourglass, but I really do not think it is necessary. However, it is all opinion, so I’m not stopping you,
  • All the other items I have not covered, I feel are pretty much self-explanatory on why they should not be bought. CDR is useless on Karthus, and If anyone wants to argue, feel free to PM me. More mana regen is not needed. Lich Bane does not work well because you want to be moving around, and stopping only to cast Lay Waste.

Guide Top

Change Log

February 27th, 2012
Guide starting to be made
March 3rd, 2012
Guide corrected, thanks to MissMaw. Thank you!
March 3rd, 2012
Changed colors because it was hurting everyone's eyes. WEAK. WEAAAAK.
March 5th, 2012
Thanks to Castermaster I made some very important changes! Thanks again for the help!
March 10th, 2012
Republished the guide due to trolls.
May 20th, 2012
Re-released the guide because the top karthus guide is really misleading, even though this guide will probably just drop anyways.

Guide Top


That is my Karthus guide, hope you enjoyed it! Try it out before you vote please!
I will be glad to explain anything in this guide if it helps. Please do not troll downvote this guide unless you have a legit reason that actually makes sense. It is in my best interest to make this guide better, so do not say LOLOL THIS GUIDE SUCKS. GIVE ME A REASON.

I'm going to be pretty mad if this gets troll downvoted.
If there is anything you really want to know, PM me, I am on almost daily! Have fun with this guide, and If anyone wants to send in screenshots for a Hall of Fame, I would be okay with that, I don't have a section right now but if anyone does send in screenshots I will add them! :)


Credits to jhoijhoi for the awesome headers!
Credits to jhoijhoi for teaching me how to use coding!