Karthus Build Guide by Badfur
Not Updated For Current Season
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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.
Hello everyone, this is a guide to how I play Karthus. I play him tanky, in the sense that, at level 18, he'll have 4514 health, and over 500 AP. Pretty awesome, eh? The common theme is surviving.
Alright, to explain the runes.
Ability Power per level for Marks and Most Glyphs is what I do, to give a nice scaling increase over time. Each level, you gain some more AP, so you hit harder.
The Quintessences and 1 Glyph of Potency are for early game power. It is to get you started on the path to damage.
Mana per 5 per level I use for all my mana using champs. It gives some base mana regen, to help with the scaling cost of spells as you get higher in level.
Alternatively, you can get Magic Penetration marks, or more mana regen. Honestly, how you do your runes is up to you, this is just what I do.
Alright, 30 points in Defense. What? Yes. Karthus is a fairly squishy champion, and is likely to get focused down by people, especially if you start doing well. To prevent this? Get harder to kill. There are many excellent masteries in the Defense tree, and I feel they are pretty much awesome.
Summoner's Resolve , Resistance , and Hardiness - Improving Summoner Spells, and increasing Armor and Magic Resistance by 6 each. Armor and MResist help you survive. It is quite useful for a little bit more protection when it comes to early game harass. I'll talk more on the Summoner Spells later.
Durability and Vigor - Health per Level, and Health regen. Well, more health allows you to survive longer, by being able to soak more damage. Increasing your health regeneration helps you stay in lane longer between bouts of harass.
Perhaps you and your opponent attack each other and are both low, or maybe you kill them. The jungler is dead, or is in another lane. The opponent probably does not have points in defense. If they do? Good for them, but here you can remain in lane, and let health regen get your health back up to a decent spot. It may not seem like much, but it is quite a lot over the length of the game. Have you ever survived a team fight with less than 10 health? I know I have. It is at points like those where I thank health regen. Long team fight, means health regen is ticking multiple times, and it, quite possibly, can be the very thing that keeps you alive.
Indomitable - Reducing incoming damage by 2. I know, not much on paper, but when you consider all the times you are attacked, it can shave off quite a lot of damage over the course of a game.
Veteran's Scars - Base Health increases by 30. More survivability.
Evasion - Reduces the damage from Area of Effect abilities by 3%. Ok, now, how many champions use AoE abilities? All of them. Every champion has at least one AoE ability. Most ults, for example, are AoEs. Taking less damage saves your life.
Enlightenment - .45 Cooldown Reduction per level. 8% at level 18. It's CDR, lets you use all your abilities quicker. Alright, so Karthus' Q and E have negligible cooldowns. That is true, however his ult is on a fairly long cooldown, and being able to use it more is always excellent. Combined with Blue Buff, that is up to 30% Cooldown Reduction. Plenty, for our purposes.
Honor Guard - 1.5% less damage. Taking less damage from all attacks = you surviving team fights. You also take less damage from Area of Effect abilities. Surviving is cool.
Mercenary - 24 bonus gold on champion kills and assists. Karthus only uses Area of Effect abilities. His ult? A GREAT way to pick up kills after a team fight, to do mass damage before a team fight starts, to make the fight easier, and help get people below the 40% health mark, so your allies using the offense tree will do 6% more damage. Assists and kills? Free gold, which is good, because the items I get are kind of expensive.
Juggernaut - I'm the Juggernaut... you can see where this is going. 3% more Health and 10% reduction for incoming disables. The goal of this tree is to help you survive. The longer you are alive, the more damage you can do.
Sorcerer's Shoes - 20 Magic Penetration and Move Speed 2. Making sure your spells do some more damage, excellent.
Rod of Ages - Health, AP, and Mana, increasing over time. All are useful for casters, and it works well with the scaling AP you get from runes. This should put you at about 100 to 120 ish AP, when the bonuses are at max.
Warmog's Armor - Health, and Health Regen. Ok, so, the goal is to survive. Long team fights? Health Regen is good, and any team fight longer than 5 seconds is going to put health regen to use. This item increases your health by quite a lot, and if you count in the 3% bonus you get from Juggernaut? This item makes you able to take a hit. That is the goal, here, surviving.
Rylai's Crystal Scepter - Health to survive, AP to do some damage, and slowing people down slightly. 15% for Karthus, but ANY amount is worth it in a team fight. This should put you somewhere shy of 200.
Rabadon's Deathcap - AP + more AP. If I recall, this brought me to 355 AP in the last game I played with Karthus. It's an item essential to any AP user, but if you can't survive long enough to do some damage, what good is it? That is why there are items like Rylai's and Warmog's, and masteries in the Defense Tree.
The final item varies. Sometimes I go Archangel's Staff, because the Mana and Mana regen are an excellent match to all the health you have. It should also give you roughly 120 AP between the 45 on the item and the 3% from your mana.
However, Will of the Ancients is also nice for a boost to AP to help not only you, but also your allies. Add in some spellvamp, it is recovering lost health, which, improves survivability.
Although, people may, and probably will in ranked, get some Magic Resistance. Here, I find a Void Staff to be useful. A tank type character like Shen, Rammus, Alistar, or Amumu might have Force of Nature, or perhaps you are facing other AP users with Abyssal Scepter. In either case, Void Staff will help pierce through their magic resistance.
Overall, I usually end up with over 500 AP and 4514 health. Pretty decent, in my opinion. However, in what order should you buy them?
To start out, everyone has their own way of doing things. Personally I aim for survivability (the common theme, here).
Boots of Speed and 3 Health Potion.
Why? To avoid attacks and stay in lane after exchanging some harass.
When I have the currency for it, I start working on getting Catalyst of the Protector. This item makes staying in lane much easier. When I get the gold, I'll either buy the next item, Blasting Wand, or buy Rod of Ages outright.
In a good game, this will be at about 14 minutes. In a bad game, around 20 minutes.
After the Rod of Ages is complete, I upgrade Boots of Speed into Sorcerer's Shoes.
Here you will want to buy a Giant's Belt and consider your options. If you've picked up a few kills, and perhaps have a killing spree going, I'd build it into a Warmog's Armor first. People will be aiming for you for the extra gold, and getting the boost earlier will be important.
However, if perhaps it's just been harass, and farming, pick up the Rylai's Crystal Scepter instead. This will give you some more health, but most notably, AP, and a slow to help you in the upcoming team fights to secure the kills, assists, and gold necessary for Warmog's Armor.
Once both of those are taken care of, start working on your Rabadon's Deathcap by buying a Blasting Wand or Needlessly Large Rod, depending on how your gold is looking.
Finish, or start working on, depending on how well you are doing, Rabadon's Deathcap. This will give you the AP to REALLY turn team fights in your favor.
After that is done, start working on the last item. For me, this is usually Void Staff, though it might also be Archangel's Staff, or Will of the Ancients
There is only one change, really, for Dominion. That is instead of buying Warmog's Armor, I get Odyn's Veil.
Odyn's Veil gives you Health, Mana, and Magic Resist, all are necessary to survive. It also has a pretty sweet ability that let's you dish out stored damage.
Alright, time for me to explain how I do things.
Lay Waste is Karthus' Q. It is an excellent, very low cooldown ability. I use it very often. Many people auto attack to last hit. I use Lay Waste It has further range, and does more damage. It also gives me more control, and provides slight vision where it lands. It can be used to check brush to see if anyone is waiting there, though the area it reveals is extremely small. In a good game, 14 minutes in or so, when I get my Rod of Ages, I can have over 100 CS, ending the game well past 200, as shown below.
I'm in mid, it's 14:28, laning against Kassadin. I've got 111 minion kills, and things are going well.
We end up winning, I finish the game with 268 Creep Score, and things were fairly well.
Wall of Pain is an excellent skill to use not only to slow people down, but to deter people from going a certain way. In my experience, people treat the wall like a gate to the ninth level of the abyss. They stay away from it if at all possible. Using it to deter people from getting close to you, or from chasing an ally, is an excellent way to use it. Even if they do cross it, they will be significantly slowed, and can be kited, slightly.
Wall of Pain has other uses, however. Since it drastically lowers the Armor and Magic Resist of those that cross it, using it on monsters like Dragon or Baron Nashor , can drastically decrease the time it takes to bring them down.
Furthermore, Wall of Pain can be used to scout. It provides vision around it, so it can be placed into brush, and be used as a scouting tool.
Defile is an amazing ability that does area of effect damage per second around Karthus. This is easily your main damage dealer in a team fight. At level 18, I do at least 200 damage per second to everyone around me. That is possibly 1000 magic damage or more per second in a team fight before magic resistance. It is an absurd amount of damage. However, you need to be able to survive to move with the fight, which is why all the health and defense. Between Defile and Lay Waste, Karthus can do an absurd amount of damage in a team fight. If he dies, Defile is still up to damage those around him. Use your ult, Requiem, if the team fight continues, to damage your enemies further, and assist your allies in taking them down. Or, use it to finish off weak stragglers limping away to heal their wounds.
Do NOT use it, however, if nothing can be gained by it. If everyone is at half health, that is still alive, and you are the last to die, using Requiem will help no one, and it will not be available for use later when you need it. Instead, keep Defile up, and spam Lay Waste to damage your enemy to the best of your ability. Also remember to use Wall of Pain so that they can't get away from you easily, and take more damage.
Alright, the reason I start with Lay Waste is because in the beginning of the game, the goal is to get gold to acquire better items, and go from there. Last hitting minions is arguably, the easiest way to get gold. For whatever reason, if enemy champs don't want to lie down at your feet and let you kill them so you can get gold, I suggest farming minions. This is why I get Lay Waste first, and max it as soon as I can.
Defile is an excellent ability, which is why I grab it at 2, and max it second. It's area of effect does a decent amount of damage at rank 1, and when combined with Lay Waste, it can easily clean up a large wave of minions. Although, using defile drains your mana rapidly. Luckily, when it is toggled off, it helps you restore some mana when you get a kill.
I pick up Wall of Pain at level 4, and max it last. Having one rank in it early allows me to do some scouting, deterring, hindering, or helping, depending on the situation. It gives me options, and some amount of control. Use it on half the lane, and you can almost guarantee people will go around it, so you limit the area where they will be.
Requiem is Karthus' ultimate ability, and I get it as soon as I can, at 6, 11, and 16.
Alright, this is the biggest point of contention that I get. Everyone always complains about Smite and Heal. People say Smite should only be used by Junglers, and Heal is meh, at best. Well, Heal is awesome, first off, and it was buffed. It has saved my life many times when going head to head to people. Or.. I get surrounded? Pop Defile, use Wall of Pain, and Lay Waste as necessary. Use Heal at around half health to keep me going, and dish out the damage.
I use Smite mostly to take down siege minions. Siege minions spawn every 3rd wave. Each wave of minions is 30 seconds apart, and Smite has a 70 second cooldown. The Siege minion is a solid target, being worth more gold. It also prevent the enemy from pushing too far. They can't sit at the tower attacking it while your tower tries to kill a siege minion. By taking it down with Smite, you get extra gold, and can keep things going well.
Need to kill Dragon , or Golems in a rush? Well, Wall of Pain, Defile, and Lay Waste (which does double damage to 1 target), and when it gets low, Smite for gold and the kill.
There are other options however.
If you are afraid to take Smite because of what your friends might think, or whatever, there are other viable choices.
Ignite is a solid option, to do more damage to other champions. Or if you know the other team has champions that have healing capabilities, I recommend Ignite.
Exhaust isn't a terrible idea, to keep people slow, and in your Defile. Between Exhaust, Wall of Pain, and Rylai's Crystal Scepter, people shouldn't get away much. I never use Exhaust on any champion, however. I personally just don't like the spell, but to each his/her own.
Flash isn't bad, if you need to do a short hop / catch up.
Teleport is a solid choice if you want to get back to lane quickly, or mop up a minion clump in another lane with Defile.
There are always option. I recommend not taking Summoner's Resolve if you don't use either Smite or Heal. Take the appropriate mastery in either the offense or utility tree as it suits your choice of spells.
This wraps up my guide / build for Karthus. If you enjoyed it, or even if you hated it, feel free to leave a comment. This is my first guide on here, and I welcome feedback.