Karthus Build Guide by CaptianMike
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Choose Champion Build:
May death free us all
+1-10% CDR (lvls 1-18)
+10 Adaptive (6 AD or 10 AP)
+15-90 HP (lvls 1-18)
Threats & Synergies
Fizz easy to deal with pre-6 but after that it is imperative that you have at least tier 1 boots, preferably tier 2 to try and dodge his ult. Since Karthus stands far back to farm, this means fizz's ult can go far and get high damage on you. Plus, he can always E your ultimate. He makes a good ban!
Although you may think he is difficult, he really isn't. He can't windwall any of your abilities and he is a melee champ. Stand really far back for the entire duration of the lane and he won't be able to kill you. He also becomes a problem if fed DO.NOT.GET.CLOSE.
Lucian is hard because he is ranged, so it's hard to poke him down, and he is very mobile so once he is on you, you can't get him off. He deals plenty of damage and is something to fear.
Easy pre-6 as with most melee champs. Simply poke her down and don't get into melee range for any reason, lest she proc her q on you. You may want to buy Zhonya's depending on how good the Akali is. All of your abilities are AoE so her shroud does nothing to hinder your power! She snowballs hard and is always relevant in the game so respect her damage and don't int. Then win!
Lots of damage and very slippery! Make sure you don't overextend because she can easily 1-shot you. Although she is very fast, she cannot outrun your ultimate. It's best to take her down with your team and use your ultimate to secure the kill if you have to.
Difficult lane! Mostly magic damage and high burst. The good thing is that he falls of late game while you grow stronger. Be patient and even if you are ahead, don't try to 1v1 him until late game
He is quite easy to beat in lane! He stays back to farm, and so do you. What's really neat is that you can kill his minions to restore mana (Your E passive). It's the perfect lane! The only problem is that if he gets his shield in time, he can almost entirely negate your ultimate so be sure to use it as soon as you know you can kill him, but far enough from him that he won't silence or suppress you to cancel it. Don't sweat this one.
She stays at a range and so do you. It's an easy lane, but when you ult her, keep in mind her small shield from her ball. She has decent team fight presence but yours is just better!
Fairly skill oriented. Her full combo can easily deal half your heal in early-early mid game. I find that Taliyas usually take barrier so don't mind trying to ult her unless she already used it. Get magic resist soon as she will punish you for your mistakes. And as with all match-ups: The late game is yours.
It really depends on the Annie. If she is good she will take advantage of the fact that her character is so much stronger than yours in early game and can zone you off. Don't get close when she has her stun and farm under tower. She has 1-shot potential at 6, unless you manage to exhaust her before hand. If she's a bad Annie, she will let you farm and she will farm. This is in your favor! You will out scale this girl hard. Getting to late game is a real task.
If fed, she will 1-shot you no problem. If not, your impact on the game will greatly overshadow hers. It's a matter of not dying to her. A lane where neither of you kill eachother is a won lane. If you manage to get ahead somehow, she is quite easy to kill!
The real problem here is that she will have a huge black shield if she goes full AP and she can use it not only on herself but any of her allies. Mid to Late game she isn't much of a threat damage wise, the problem is that a single Q on you can ruin an entire team fight. If you can't position right or get blown up before dealing damage, you can count on that being a lost team fight unless your team is fed enough to 4v5. She can easily assist her jungler in killing you with her everlasting Q and Black Shield. Just play safely and position correctly to win.
You don't have any movement abilities so her W Miasma won't hurt your kit, but she does deal a lot of damage. Watch out for her power spikes at level 2 and 6. Otherwise, look away from her after you use an ability. If you're constantly turning you head around, the odds that her ult will hit are low. Ensure she doesn't get ahead; better to play safe and lose some cs than give up kills.
Ah, Gankplank. He is actually not easy to win against. He also has great teamfight, can cleanse your CC, and heal for % missing HP. His barrels deal a ton of damage and usually it's not worth it to try and destroy them with your auto attacks since the travel time on your auto attacks is quite slow. If he gets a couple kills.. it's going to be a difficult time.
Punish his level 1 with your q, but back off if you're low. His passive makes it easy to kill low health targets. It's extremely hard to come back after he is ahead due to the fact that he can dive you very easily. Be very careful of his level 6. Get Zhonya's hourglass after tear. Once this item is finished, he will have a harder time killing you. If he is fed, he won't even need his ultimate to kill you TL;DR- BE CAREFUL. You contribute more to fights than he ever will. Just outscale him.
Vladimir is tricky because he also is a late-game scaling mage. He contributes to team fights as much as you do! He can also dodge your ultimate with his W. You might be able to kill him pre-6 if you manage to land your Q just on him numerous times. This is very important and can totally shut down Vladimir. If he is fed, he can tower dive you because he is very fast. Skill oriented match-up. ***Remind your ADC to get executioners calling***
Early game is your best window to build a lead on him. He is extremely vulnerable pre-6. Post-6 keep your distance away from him, as he is very mobile can make quick and deadly trades. He is difficult because of his extreme mobility, which only gets faster as the game progresses.
He pushes the wave extremely fast, and it can be difficult to keep up. Laning should be easy, be sure to poke him often with your Qs as he is immobile and melee. Mordekaisers usually build Gunblade, in which case you absolutely cannot fight him in Melee ranges. As long as you kite him, you should have no problems at all. He is very squishy.
Dodge his Q to win the lane. Both of you have global presence, but overall he roams better. Karthus has a much better teamfight overall. Skill match to win lane, but you're way more useful in teamfights.
Stand behind the minions to avoid her Q's. It can be hard to farm under tower due to her strong poke, so you should aim to clear the wave as quickly as possible. Before you Ult her, remember she has a shield ability!
Threats & Synergies
Easy farm lane. You might not be able to kill him, but that isn't your goal. Your only purpose is to farm. You need to keep in mind his own ult because he will try to save his allies. Make him use his ult first, then you go. His ult is on a slightly lower cool down than yours though.
I hate riven. She is mobile, tons of AD, and shields that will make you cry. It's no use to try and ult to kill her as she can block most, if not all of the damage. She snowballs really hard. Your goal this lane is to not die. Get farm is you can but the number 1 priority is not to die to her pre-6. She isn't as much a threat later though so try your best to outscale her.
He can't interrupt your R, but he can usually survive your R because his oranges heal so much, especially if he is low (it does % missing hp heal). He dishes out a lot of damage which is hard to dodge due to you being immobile. Take caution and look to use your ult in other lanes throughout the game.
.Stand really far away from him in the early levels, because he can deal half of your health with one combo. You eventually will be able to 1v1 him in the mid-late game, and you'll be a superior threat in team fights as well. Another matter of simply out scaling. You can buy Rylai's to make him more manageable.
Very difficult, especially when fed. She has long range engage and is strong all throughout the game. I would recommend exhaust.
This lane is hard. He will push you in and poke with Q. He is tanky enough that he can dive you easily. Play with extreme caution and farm.
It is nearly impossible to hit yasuo with a Q during the laning phase due to his insane mobility. He is very hard to deal with if fed. Let him push the wave to you so you can farm under tower.
Super easy pre-6 if you can dodge his axes. He has no mobility movements besides his ultimate. If you land isolated Q's on him, he will melt. This should be an easy game if you can make Olaf irrelevant
New Aatrox is interesting. He has a few movement abilities, but if you dodge his first Q, you will be able to run away from him due to Aatrox's Q animation taking a long time. Keep your distance and look at his items to see when he gets boots and/or phage. Once he gets those items, you should stay farther away. Before then, poke him as you please!! Not a hard lane pre-6.
Karthus was buffed on 8.21 :)
Are you tired of enemies escaping with 1 hp? Are you tired of falling off late game and being useless? Do you like having the last laugh!? You've come to the right champion. Karthus is a champion unlike any other!
- Very strong mid and late game!
- Strong team fighting!
- High damage output
- People always underestimate you
- Useful even after you die
- Still good even when behind
- Stacks tear insanely fast (If not THE fastest)
- Great waveclear with 2 AoE abilities
- Weak laning phase
- Needs items to be useful
- lacks hard cc
- Mana hungry
- Literally no escape besides flash
- Damage is dependent on hitting Q's
After trying many combinations, flash and exhaust are my favorite. I've tried to run TP and it is good for the early game but in the mid to late game, you lose out on dueling potential without exhaust. However, for top lane I would recommend TP for overall map pressure. If your mid laner takes TP, then I would take exhaust because I love to duel. Ghost is ok, it can be viable some games but most of the time I would not recommend it. You need flash to avoid ganks and quickly reposition in fights. Ghost can be useless if they have a Jarvin on their team or huge displacement ults like Gragas. 99% of the time if you get Rylai's it's just as good as Ghost.
|The Rod of Ages is a very strong item on Karthus as it gives him all the stats he needs: health, mana, and most importantly ability power. Build this item first in order to get the stacks as soon as possible.|
|The next item that you should try and build is the Archangel's Staff. This will give you loads of mana plus a juicy 80 ap. The real reason behind it is for when it transforms into Seraph's Embrace. The shield lets you bait enemies into fighting you. It's very useful in team fights when a predictable burst will hit you (I.E. a lux ult, or a Darius ult) so you can soak most of it up. If you are taking tower shots, use this item to negate a shot or two. It's personally my favorite item to get on a caster mage.|
|Rabadon's Deathcap is a self-explanatory item- pure power. Get this item 3rd if the enemy team is really squishy so you can kill carries as fast as possible.|
|Otherwise, Rylai's Crystal Scepter is the next best option as the slow lets you hit your Lay Waste much easier and once the enemy engages they won't leave until they are dead.|
|The perfect synergy with Rylai's is Liandry's Torment. Your E Defile will dish out a solid amount of magic damage even to tanks due to the % current HP passive on Liandry's- Which is twice as effective due to Rylai's!|
|Zhonya's is a great item against assassin's like Zed or Talon. If you fall at all behind against an assassin or a one shot mage like Syndra or even Lux, you should buy this item. This item gives you survivability and outplay potential if you use it correctly. Don't be discouraged if you don't know how to use it at first. It takes practice to truly use this item effectively.|
|Pretty straightforward item now- get this item if your opponents have heavy healing. ALWAYS take this item against Dr. Mundo and Vladimir. Otherwise, keep an eye on enemy's builds. If they are building items like Bloodthirster or Ravenous Hydra, consider building Morello's if those enemies are fed.|
|According to lolwiki, this item becomes gold efficient if your opponent has 90 magic resistance or more. If your opponents built items like Maw of Malmortius or Spirit Visage, I would buy this item. Don't make the mistake of buying this item if you opponents aren't building and magic resistance! It's better to build AP if they have no resistances. Some champions, like Jax can get magic resistance from abilities ( Grandmaster's Might) so take that into account when calculating how much magic resistance your opponents really have.|
The second tree I chose inspiration. There are plenty of options in this tree, so I would encourage you to pick ones that suit your style- that's what these runes are all about. I personally choose Magical Footwear and Perfect Timing. Future's Market is another good option.
Another viable option is the precision tree. The new Presence of Mind helps with ultimate CDR and there is damage boosting runes at the bottom of the tree such as Last Stand and Coup de Grace (pronounced "Coo Deh Grass" if I am not mistaken)
This is the laning phase. Your strategy for laning will change depending on the matchup. Is your opponent mobile, like Riven or Yasuo? Don't push or they will freeze the wave and leave you susceptible to ganks. Instead, match their push or simply farm under tower. Are you against a tank or immobile fighter? You should be focused on poking them with your Q Lay Waste. Look at the health of your own minions and you can predict when they will walk up to cs, then you can more reliably hit your Q. Do your best to make sure the minion is isolated, so you can deal double damage and ensure the last hit. Take into consideration of the slight delay in your Q or you might miss some CS. Once you hit 6 make sure to check on other lanes to see if you can ult for kills. Generally this is how you'll be getting all your kills early game. Your goal here is to CS as much as possible and die as little as you can. If you wish to push the lane (right before you recall, or after you kill the enemy laner) you should Q all 3 of the caster minions until they die then carefully last hit the melee minions.
At this point there might be small skirmishes and roaming champions everywhere but you still have not reached your maximum strength. Depending on how fed you are, you might be able to 1v1 the enemy ADC assuming you can hit a couple Qs. Still, focus on going to any lane with big waves to get CS. You can go for some kills at this part of the game but more often than not, you really should just be playing safely still until late game where your true power shines.
AKA you have 4-5 items.
You are a very powerful champion and better yet others have fallen off at this point. Your mission here is to dictate and win teamfights. You can use your Wall of Pain to catch an enemy out of position for an easy engage with the 70% slow it gives. Once they get in your Defile range, they will be dead. Know that a lot of your damage comes from your Defile so you want to be close enough in a fight to have your E ticking on enemies but far enough that you won't be assassinated.
If you find yourself setting up for a teamfight and both teams are in the poking phase before the fight begins, use your Lay Waste relentlessly as it has a low cost and cool down yet dishes out a lot of damage. Don't be afraid if you Lay Waste and the target isn't alone for the double damage. Any damage is good damage. Now the team fight begins. Your role is to stand back and take out the highest priority target in your range with your Defile and Lay Waste. If your target dies, repeat with the next highest priority. If you know you will die soon in a fight walk straight into the enemy team. Yup, that's right. Run right into them and give them pain! Your Defile will constantly be doing 100s of damage and once you die you can safely cast Requiem without being afraid that CC will interrupt it. Do not be afraid of death. That is the difficult part of Karthus sometimes. Be real with yourself and if you know there is little hope of an escape, go in and die to deal as much damage as you can so your teammates can finish off the fight. This is so important that I would even Flash into the enemy team to get their backline in the damage too. Remember, you are death.
In depth answer: You may want CDR for your ultimate Requiem, but in reality, there are few times in a game where you can use your ultimate effectively. If you use your ultimate that seldom, it is clear that you don't need CDR to repeatedly use that ability. Also, Defile becomes a huge source of damage in the late game but it is a toggled ability so it doesn't scale at all with CDR. Finally, if even after that you still want to grab an item with some CDR, your purchase won't be 100% cost efficient. You are paying for that CDR when you won't even need it so therefore, you should stay away from CDR items in most situations.
WITH THAT BEING SAID-
After doing many mathematical calculations, I discovered that building CDR is viable. The main reason for doing this is to get Lay Waste cooldown lowered, so it can be spammed even faster. The results from my calculations are simple. If you can land your Qs, build CDR. If you aren't good at landing Qs, then this build which has more AP will be better. The exact cutoff is that if you can land 47% of your Qs or more, it's better to get CDR. Note that CDR builds have less AP overall so your ultimate won't be as strong as you may be used to. I recommend checking out Ding D-ng's guide for good CDR builds and playstyles.
TL;DR- If you're skilled, buy CDR.
-You can convert mana to health at an affordable cost if you have at least Tear of the Goddess and Catalyst of Aeons. If you keep Defile on, it costs mana which is converted to health, and part of the mana spent is refunded. You heal up to 25 health per second!
-You may deactivate your E Defile while recalling and your recall will not be cancelled.