Karthus Build Guide by Izacmizac
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.
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.
Karthus is one of the games most difficult champions to master and in some cases play. This guide will show you how to play him, how to lane with him, and how to use his skills effectively.
- Deals large amounts of damage quickly
- Excellent at picking champions off who are low
- Excellent mid champion
- Cheap as HELL!!!
- Very Squishy
- Hard to play
- Hard to get out of battles
- Mana hungry (if you spam your E which is an AoE)
So if you have chosen to continue reading you should now understand that karthus won't be an easy champion for you unless you have amazingly awesome talent(which is possible) you are going to have to work hard. If you would like to play an AP carry and be extremely cheap and make people extremely mad at you then you should continue reading. If you are just here for the build maybe skip to the item build chapter.
So for masteries i have taken the usual caster masteries. Taking ability power in offensive and sacrificing 1 point in critical strike so i can get cool down reduction, followed up by a magic penetration. I spent the rest of the points in utility getting health and mana regen, cooldown reduction and base movement speed.
So for runes i have taken the normal caster runes. Magic penetration marks as per normal so that your abilities can get through some of that magic resistance. Mana regeneration seals so that you don't run out too quickly early game(hopefully not late game =p). Ability Power per level glyph's so that you start off with a bit of ability power and get some more as you go on. I find the ability power per level works better then just strait ability power because you end up with more at the end of the game. Finally flat ability power quintessences so that you start off with yet more ability power.
I took flash because as a squishy caster you need a method of escaping and flash is an excellent way of doing this. Flash can be used to flash over walls to escape as well as just plain flashing in a straight line. I chose teleport plainly because if you feel like you don't need clarity, then teleport is another great option for quick little back to base trips or teleporting to mushrooms that Teemo has lain.
Some Other Useful Summoner Spells:
Now for these i have chosen flash in both because of its escape mechanism but the reason i have chosen. Clarity is really a spell that some people don't often choose but i would recommend it for newer players because you may not have the mana regen runes, or you may in any case just need it because you might be running from a battle and be out of mana and in need of some to escape using your W etc. The next choice is ignite now ignite is possibly a hard spell to run for newer players but in some cases it isn't. Ignite is an option never the less, it can be used when you are chasing someone down for instance using it in conjunction with your W for a slow or when you are 1v1'ing someone and your using your E and Q.
Early game Karthus's Q is by far his most important skill because it is easily spammed and can be used to harras the enemy champion. It is excellent at scaring the enemy champion away. His next most important skill i believe to have before his ulti is his E because it is excellent at distributing AoE damage to minions or champions in conjunction with his W and Q. Get your ulti whenever you can 6,11,16 because it provides excellent support to your team if they are in team fights and need the champions lower on life or in the case that a champion gets away.
Karthus i believe really only has one way to build him because he can't be built tanky and he can't be built with AD. He can be built with mana, AP and in any case some health to top it off with. Grabbing armor is a waste of time in my view because Karthus can use his passive however in some cases that you may need to get a Quick Silver Sash because of High CC but thats the only tanky item i would really recommend. I am going to recommend some different AP builds.
Karthus is a very slow champion and is easy to chase down for a kill. So by getting boots of speed first it ensures you the added advantage of getting away from early ganks if they have a jungler/roamer or just your team won't call mia's. Also because you are using runes you will already have 18 ability power at level 1 and it will grow to aroudn 40 at level 6. Getting 3 health potions is also helpful because you are so squishy you will lose health easily and need to regen it quickly. Plus you won't need mana pots because you already have cleanse and mana regeneration runes.
Sorcerers shoes in my opinion are the best type of boots to get for karthus because they provide speed as well as magic penetration, which you will most likely need because teams tend to build magic resistance when they see an enemy karthus. As mentioned above Karthus is extremely squishy and mana hungry so the next core item is Rod of Ages and i believe it to be a must have item because it provides extra mana and health as well as ability power. Not forgetting its passive, on leveling you receive a certain amount of health and mana regenerated back.
Builds vary between different Karthus players so i will provide you with some options you may take and some examples of finished builds.
Just before i give the example i would like to point out a few items that may be giving players grief, Mejais soulstealer, quick silver sash and banshees veil.
When should i use Mejais Soulstealer?
This item is for confident Karthus players who believe that they are able to get kills because it runs off kills. The more kills or assists you get the more ability power you get. It can also be used after you get your sorcerers shoes because at around level 6 or 7 you can be reasonably confident in your team and if you are going to get a lot of kills or not.
When should i use Quick Silver Sash?
Quick Silver Sash is an item that i would normally not recommend to Karthus players because it doesn't help him in any way really. However i use it when i am playing against a team heavy in CC's or if i am playing against champions who have CC's and are good. These champions include: . Otherwise i would not recommend this item.
When should i use Banshees Veil?
Banshees Veil is a good item for new players because it provides some mana and health once again as well as some magic resistance and a shield from spells. It is useful when you are playing against players who are going to do a lot of damage to you through their abilities, usually the same champions mentioned above.
Items to Consider:
catalyst the protector
Early game is rather not the best for karthus. He really only starts to hurt around level 6 when he gets his ultimate because he is able to start getting some cheap kills. However when i play Karthus early game i usually get my Q spell first and i make a bid for mid because all Karthus's should mid. Once the minions have spawned i start to harras the enemy champion at mid using my Q because of its low cooldown. I find that just spamming your Q trying to hit the enemy champion with your Q while there is no minions near them so it maximizes the damage. Once you hit level 3 you are able to try and pick p a mid kill. Using a combination of using your W to slow them then chasing them down spamming your Q lowering their damage and if your close enough use your W for the AoE damage. If you are not able to pick up early kills try and just sit back play defensively and farm on some minions, or you could try and call for a gank on mid if you have a jungler it makes it easier for this gank to happen. Remember though you are squishy so don't get yourself into any tricky situations try to play it safe and don't over extend until you are confident you have a kill or you have some wards in the river etc. Once you hit level 6 i usually go back to the base to buy my items but more importantly tell your team to look out for people who are low and you yourself look for people who are low so you can use your ulti. Karthus's ulti is an excellent power for your team to have.
Basically i find early game is quite boring for karthus players if you don't get kills because otherwise you are trying to play defensively waiting for your ultimate.
Mid game is when i really think Karthus shines. You should have finished your rod of ages and be doing some nice damage now. So by now the game has progressed and you should be grouping up and trying to push lanes. Well the best thing to do now because you are terrible at pushing lanes and you can't go out by yourself because you are so squishy. So what i do is stay with my team and assist in getting kills most likely you will be getting a few of them.
By now you should know if you are going to need a more complex build or if you are going to stick with a simple AP build. You should be looking for those annoying CC champions to see if you need a Quick Silver Sash or not and you should be looking out for the enemies AP carries to see if you need a Banshees Veil. If you find yourself in a situation where you need a Quick Silver Sash or a Banshees Veil try not to stay with the tank on your team at all times because it is hard if they have heavy CC and if they have a good AP carry its hard for Karthus to stay alive long if he is by himself.
So now during mid game i would usually be looking out for people to ulti because you are doing so much damage. The enemies are probably scared of you too so use that to your advantage. If you see a squishy looking easy to kill and you have a Teemo mushroom or a ward close to it teleport there and kill them its always good to pick up a few easy kills. JUST REMEMBER what i was saying before i know i way be contradicting myself right now but its a good idea if you know where the enemies are. If you know they are all top having a team fight and your team doesn't need you and there is a squishy champion bottom, go get the squishy and maybe by then the team fight has progressed and you might be able to pick up a few kills with your ulti.
What can i say about late game? Its either you fall apart because the enemy team has tanks that can't be killed and you are just a chew toy for them. Or you had such a great early and mid game that you are just owning them. Either way what i have already said still applies try to stay with your team, there's nothing worse then a Karthus who keeps trying to solo people who he can't. However if you know their team is squishy and your are unstoppable then go right ahead just pick your fights. Don't try to 1v2 because you will almost always die, and the chance you live and get a double kill is most likely your judgement.
Games generally don't drag on for very long and its up to you to stop them. So really there is nothing more i can say on the topic of late game.
Team Fights, this is the bane of my Karthus playing. Depending on the way you play him Karthus can either be useful in team fights or just a waste of space. Try to sit back for the beginning let your tank/tanks initiate and your team to go in before you attempt to fight. I always try to sit at the back spamming my Q and once they get a bit low i go in using my E for AoE damage on all of them. If your lucky enough to have a champion like Amumu on your team then thank your lucky stars because his ulti and your E is a great combination because Amumu's AoE stun keeps them there long enough for your AoE E to deal a massive amount of damage.
Once the team fight has turned into a chase you should check the running enemies health to check if you can get a kill or two with your ulti. Using your ulti at the right time can prove to be a useful tool in the box for you team.
When should i use my ultimate?
Karthus's ultimate is usually used to pick off those running champions who think they got away. However in an instance of a team fight and you don't have a tank to initiate then it can be used as an initiation tool because of its high damage. I would not recommend this however it is possible. This should never be the case but unfortunately you will get teams who don't pick tanks.
I hope you enjoyed this guide on how to play Karthus because i have most certainly enjoyed writing it and i hope it helps you on your way to mastering Karthus. If you love to play Karthus i would love to hear what you thought and how i could improve on my guide. I encourage constructive criticism. Thank you for reading my guide and i hope it has given you a few tips on how to play Karthus and maybe a good item build.