PREFACE TO DEATH CAN'T STOP ME:

UPDATES:
-10/9/10- Added a few more tips to the "TIPS" section. Removed the first few typos that I saw. Added a "Champion Synergy" section to help you build a solid comp for an arranged game.
-6/28/11-Fixed current patch info for Karthus. Primarily the nerf to Requium. Updated the appearance of the guide. Some of the information may still be outdated. Currently though I believe Runes/Masteries/Items are all up to date. Some of Karthus' ability info might still be out dated, however I do not feel that (at this time) those things lacking make this any less of an extensive and well thought out/written guide.
7/24/11- Retooled the guide to make it more visually pleasing. Dropped out old outdated icons and put in the new ones.

Karthus "The Death Singer" is a champion that many people underestimate. Not that they think he is weak but they feel that people only play him for the soul fact that his Ulti is probably the most infuriating ultimate in the game.
Many times people breathe a sigh of relief after a teamfight and they think they've escaped just to be killed as they almost make it home safe. They spurn his name and they call the people who play Karthus a variety of terms that aren't safe for children's eyes or ears.

With this guide I hope to illuminate the many utilities Karthus can provide when played in an arranged team.

Pros:
-Brings debuffs and a slow in one spell
-Superb damage
-Ultimate is a great Initiator OR Finisher
-Synergizes well with many champions
-Superb tower defender
-Mana effecient with Lay Waste last hits.

Cons:
-Squishy early game
-Ultimate is hard to time at lower levels
-Defile can sometimes OOM you and prevent your passive from being used to its full potential.
-Accidental KSs happen.

Summoner Abilities:

These are up to you. I prefer Flash and Teleport

Flash is a must have ability on a lot of champions. The predominant reason I take it is for positioning purposes. Getting caught alone is never a good thing, flashing over a wall can often save you.

Teleport is an amazing utility summoner. I believe it's sometimes under-rated at how effective it really is. Great for defending towers, pushing towers, re-joining your team, back dooring etc. etc.

Other Viable options are Ghost Ignite Exhaust .

Ghost will give Karthus an even more impressive kiting ability. Ignite can help in team fights against heals or life steal/spell vamp. Exhaust scales better into late game than Ignite, it's a great summoner to have if you're getting focused by an anti-carry.

Champion Abilities:

Death Defied(Passive)- Upon dying, Karthus enters a spirit form allowing him to continue casting spells while dead for 7 seconds.
Lay Waste- Karthus seeds a bomb at the targeted position. After half a second the bomb goes off and deals magic damage to nearby enemies or double damage if it hits only a single unit.
Cooldown: 1 second
Range: 875
Cost: 20 / 28 / 36 / 44 / 52 mana.
Magic Damage: 40 / 60 / 80 / 100 / 120 (+0.35 per ability power)



Wall of Pain- 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 7 seconds.
Cooldown: 22 seconds
Cost: 100 mana
Range: 1,000
Wall width: 800 / 900 / 1,000 / 1,100 / 1,200
Magic & Armor Reduction: 15 / 20 / 25 / 30 / 35
Slow percentage: 40 / 50 / 60 / 70 / 80 %

Defile- (Toggle): (Off): Karthus steals energy from his victims, gaining mana on each kill. (On): Defile drains Karthus mana to deal damage to nearby enemies each second.
Cooldown: 0.5 second
Range: 450
Cost: 30 / 42 / 54 / 66 / 78 mana per second.
Mana restore: 20 / 27 / 34 / 41 / 48 Mana
Damage: 30 / 50 / 70 / 90 / 110 per second (+0.25 per ability power)

Requiem- After channeling for 3 seconds, Karthus deals magic damage to all enemy champions(regardless of distance).
Range: Global
Cost: 150 / 175 / 200 mana.
Cooldown: 180 / 150 / 120 seconds.
Magic Damage: 250 / 400 / 550 (+0.6 per ability power)

Masteries: A standard 9/0/21 caster mastery. I prefer movement speed increase over improved neutral monster buff duration. You can switch the points around if you wish. Improved Flash and Improved Teleport are taken for obvious reasons. Beyond that it is purely up to you how you go. Mana isn't a big issue and I prefer having a bit of an EXP edge especially when i'm mid.

Runes: A basic caster set, some Magic Pen marks, AP per level Glyphs, Flat AP/AP per Level or Mana Seals, and Flat AP Quints.

Core Items: The core items are what I feel will make Karthas strong. With them you've hit your late game stride.

The core items are-
Archangel's Staff
Will of The Ancients
Rylai's Crystal Scepter

Additional Items: These are items that you'll pick up anyway, they have their own place.

Sorc Boots
Rabadon's Deathcap
Void Staff

Alternatives For Items:
Depending on the enemy group comp you are facing or how well you are doing alternatives for items include:

Banshee's Veil
Merc Treads
Quicksilver Sash
Zhonya's Hourglass
Mejai's Soulstealer

Mid Lane Tactics:
A well played Karthus at mid means that your tower receives little to no damage between levels 1-9. Also means you're able to send the person you're laning against back to heal once or twice before level 9. I'd prefer getting a few kills at mid early but pushing the lane is just as effective. Some things to pay attention to while you mid.

- Depending on who you're laning against you may choose to be more defensive and simply focus on last hitting minions. Champions like Mordekaiser and Katarina can pose problems. Katarina's high burst and in and out play-style reduces your chances of laning for an extended period of time. Mordekaiser simply can generate Ironman off of your minions making your harasses do little to no damage. More often then not you're doing no damage. With that said, they are not unbeatable mid. As Karthas you have plenty of tools and abilities that make you a threat to any champ you lane against mid. Use your abilities with purpose. Last hitting minions is your key focus while mid, so if the person you're laning against stands too close to their minions place your Lay Waste underneath a minion and deal some splash damage which they might not see coming. Your opponent tends to move around a lot? Place your Wall of Pain in their path and start leading them with Lay Waste. Lay Waste + Defile 's passive means you can lane indefinately with conservative ability use. Champions I tend to have great success laning against: Teemo, Twitch, Corki, Nidalee, Miss Fortune, Ashe, Karthus. Lay Waste generally out ranges all non skill shot champs. Keeping Teemo's and MF's move quick turned off isn't difficult it simply takes timing. Placement of a bomb behind your enemy as you move forward is an easy way to force them into some damage and remove their movement speed buffs.

-Always pay attention to your mini map. Call MIAs and hope your team calls them too. If you feel a bit over extended back away and let the minions lines push to a more comfortable position. Karthus is not much of a turret killer with this build however you can farm minion waves allowing your minions better access to the enemy turret which they can successfully weaken over time.

-After hitting level 6 you should openly communicate with your team. Let them know you have your ulti, ask if anyone they have in their lane is low. Ask for them to call out if they nearly kill someone and are willing to feed you the kill. Ask if they want you to come aid in a gank. Be proactive, farming is helpful to you but not directly to your team. If your team calls for your ulti and you have no magic pen items yet quickly try to see your enemies HP if they are still visible. Nothing is more upsetting then seeing an enemy with 150 HP left and your utli hits them for 120 due to magic resist. Early on it is better to assume your ulti will do anywhere from 50-70 less damage due to resists. And then you adjust accordingly.

-Don't be afraid to use teleport. If you are forced to retreat to your well then teleport back to mid when you can. If your team has wards down in prime locations teleport onto them and set up a gank.

-Death for Karthus is not the end of the world. It's simply an extended time for you to DPS, slow, and or ulti the enemy. Use your passive to your advantage. Tower at 1/2 health and about to be pushed? Teleport on top of it and let them tower dive you. Place your Wall of Pain directly on top of yourself, pop Defile, spam Lay Waste until they kill you. Did you get them low? Ulti them tada you'll probably score 2-3 kills depending on how long they stick around inside your defile after you die. I'm not saying always sacrifice yourself in those situations but if you can make them pay for a push DO IT. Within your own judgement of course, if you don't think you have the damage to do it then dont.


Early Game Levels 1-6: Start by grabbing your mana crystal and a health pot and make your way to mid. Sit by your turret and wait for minions. Begin by last hitting minions until you are level 2 where you grab Defile. Once you have Defile you can be a little more agressive in harassing your opponent at mid. If you run low on mana last hit with your auto-attacks to get your mana back quickly. Follow the ability guide and grab Wall of Pain at level 5. Let your team mates know you're close to having your ultimate. Level 6 you have your ulti, if you've been harassing your opponent and they are about half health push them a little more. If you have the mana you can Flash, Wall of Pain behind them, Defile, lead your target with Lay Waste. If you think your ulti will finish them then pop it. Route 2 is to simply move into mid game. Keep farming and wait for your team mates to call for your ulti if they want it.

Mid Game Levels 6-13: Hopefully by now you've got your Soul Stealer and your team mates are feeding you kills or assists to build stacks for it. Around level 7 you can grab Golem buff. Simply put down your Wall of Pain turn on Defile and Lay Waste spam until it dies. This is also when you can start ganking, around level 10 you should be able to get your Tear of The Goddess. The best way to set up a gank is to let your opponent mid see you b back to base then teleport out where you want to set up a gank. Be aware of your enemies positions if they have any junglers or MIAs then perhaps you're better off playing it safe. Between levels 11-13 you should be working on your Sorc Boots and or Crystal Scepter. Yes a bit late for boots but up to this point you're working with your team while they are in separate lanes. The magic pen early on can be beneficial but they are a rather cheap item and are easily paid for with a few minutes of farming.

End Game Levels 14-18: Team fights should be your main focus. DO NOT INITIATE with Wall of Pain . Let your tank initiate, place Wall of Pain as the fight begins so that it passes through as many enemies as possible. Make sure you've got Defile going and try to target squishier enemies with Lay Waste. If your team needs a bit more of a boost in the fight pop your ulti in the middle of it (out of range of silences and stuns) it could be the little boost your team needs to finish the team fight and you could score multiple kills/ assists. If you start getting focused keep Defile off until you're sure the danger is over or if you're killed. Make sure your team fights on top of you if you die because you'll be able to contribute. The reason I say turn defile off if you're getting focused is that it sometimes glitches and you won't be able to cast any abilities when you're dead if you're OOm.

SIDE NOTE: This is primarily a guide. There are some tips here and there scattered about, I attempted to provide as much information for you readers as I could but I do not expect this guide to make you the best LoL player ever. It is for arranged games where your team will let you flourish and aid in getting your Soul Stealer stacks up early (if you go the Soulstealer route).

Skills To Practice:
-Last Hitting Minions
-Map Awareness
-Proper placement of your Wall of Pain during a gank, team fight, turret defense or escape.
- Using your ulti as an opener OR finisher. (Finisher being the thing you should worry about more)

TIPS:
-Karthus is a superb harasser, use this to your advantage once you've gotten last hitting minions into a some what natural rythm. People tend to become over confident when laning against Karthus. His low HP and seemingly laughable damage with Lay Waste early game makes them want to push you back to your turret. This is not terrible use it to your advantage. The best time to use it to your advantage is level 5 once you pick up Wall of Pain. If they get too close then press the advantage. The distance they have to travel is your friend. Put your wall behind them and charge on in (assuming your mana pool is 75% or higher) turn on defile and force them to fight. You might even get a kill out of it, your intent is to turn what they thought (you being passive and weak) on it's ear. Make them the passive one. Also them over extending often means you have a prime opportunity to gank them with a friend or two.
- Karthus is not a front line, in your face, I got you by the balls champ in team fights. He is the Marine Sniper a mile away with a Barret .50 caliber long range rifle and enough training to make the proper mathematical and atmospheric calculations 100% of the time; thus resulting in the death of an enemy by removal of the area from the neck up. You can aid in initiating with your tank by using Requiem . Once the battle is in full swing you can slip your way to the outskirts of the battle and turn on Defile . Throw your Wall of Pain in so it hits the maximum number of targets OR save it for when enemies try to flee or chase. The slow and debuff will boost your, as well as your teams damage dramatically when used during a team fight. Spam Lay Waste within the fray. If you must jump head long into the fight then be aware of your mana and HP. When you see your mana drop to about 50% turn off Defile (assuming you weren't focused down already). Keep using Lay Waste and finish with Requiem if you didn't use it to aid in initiating.
-Defile is a great deterrent if a melee champ decides to chase you. Damage over time ticking upwards of 200 damage a second mid to late game can make someone think twice about trying to score a kill against you.
- A lot of the time in my games as Karthus I see people afraid to walk through Wall of Pain . Yes it is a slow, yes it is a debuff but the hesitation it seems to generate astounds me. 3 champs want to jump your turret? Wall of Pain in front or lay it in front of your turret to deter them. It has bought me 10-30 seconds of hesitation from the enemy which can be enough time to set up a gank. They fear the fact that passing through it will put them into a world of hurt.
- IF you're using this guide in a normal SOLO game it can work too. If you get to the game screen and no one has chosen a tank, if you haven't locked in and have a tank that you can play with serviceable runes then do it. Because as well all know a Tank is a great thing to have on a team.
- For Ranked Matches I do not recommend the Soul Stealer based on the fact that most of the time you will be the first to die if the enemy has a shot at taking you out. That is how ranked matches go. Build a Rod of Ages if you're doing a ranked game to help out in the leveling process. (Nothing more refreshing then dinging to level 8 and having a chunk of HP restored when you were about to die)
- Ganking is a great way to relieve pressure on a friendly lane while applying pressure on the enemy. Setting up a gank is not as easy as it seems. It takes proper baiting, I don't mean 1 person out in the open dancing for the world to see. Ganks require coordination. They also require your enemy to over extend. Ganks mainly work when the enemy team has little to no communication, of course that is hard to come by in arranged games. The best thing I can prescribe is whichever lanes needs the most attention when one of the friendlies in the lane has to B they should grab a ward and place it nearby. The bushes can work but any place nearby where the enemy won't possibly see you coming. The best thing I can suggest is call for a gank after you leave mid to heal or buy an item. Teleport in on your ward and wait briefly. If the enmy seems to be very aggressive then you can profit from the gank. Your team just has to play back and feign weakness. The most obvious tell that a gank is incoming is the bait showing confidence. Once the enemy over extends a little, walk in. They will probably pop whatever escape skill they can so wait for that. Generally speaking against a champion like Vlad I wait for him to blood pool before I use any kind of CC with any champ. Karthas thankfully can slow and debuff. Coordinate with the lane and if they have CC let them use it to help. Beyond that it is about skill usage and proper placement of your skills. Weather you shut the enemy down quickly or if they have just enough HP to get away it's about working together. If they do get away with barely any HP your ulti can make the gank worth it. Don't get discouraged if the enemy makes a comment about your failed gank. Or if you succeeded and they say something like "Oh so it took 3 of you to beat me hahahahaha" remind them it is a team game and gank them with all 5 of you next time to drive the point home. Ganks are a part of LoL and can lead to a strong push on a turret that needs it.

-CHAMPION SYNERGY:

-Galieo- Galieo's Idol of Durand + Requiem in a teamfight is an amazingly devestating combo. He is a champion that I generally prompt my friends to play if we are doing an arranged.
-Morganna- Believe it or not but her ultimate plus your Wall of Pain and Defile can make for a nasty combo. You can help keep them in range of her ultimate with your slow on top of her's and the damage you'll be putting out will be rather solid.
-AP Kennen- His stun facotry of an ultimate plus your Wall of Pain and Defile will wreck an enemy comp. It takes a lot of coordination and positioning but it can be a great combo.
-Nuke/Support Zilean- Something I would never certainly want to face in a 2v2 is a Karthus with a Zilean. Slows, Nukes, Debuffs, AoE, AND a guardian angel on call. Slow Spam/ Time Bombs and enough AoE damage to devestate most squishy champions and probably even hardier champions.
-Amumu- Sure his ultimate doesn't do a load of damage but it does set you up to help slow enemies and keep them in your Defile for awhile. It's another solid combo.
-Nunu- His ultimate does to a sizeable chunk of damage as long as people stay inside of it so why not help keep some pesky enemies in it as long as possible AND reduce their MR. Wall of Pain as many of them as you can and watch them get nuked.

Closing:
Karthus is a well balanced champion. He does take skill to play, the understanding that your ultimate is not as strong as you think it is early game will allow you to score the kills you want to with it. You just have to overcompensate. This will let the enemy team see that you know what you're doing and not have what seems to happen often with a new Karthus player they blow a little too early and get laughed at ;D. Karthus will infuriate the enemy over and over again, just don't get upset if you pick him up and aren't able to destroy the opposition.

Suggestions for LoL players that are not Summoner Level 30 yet:
-Mastery wise you will want and need your magic pen above and beyond anything else. So for those of you who are level 9 and up grab the standard offense caster masteries 9/0/0 so you get that extra 15% magic pen.
-If you like ignite on Karthus then grab the improved ignite if you are level 10-20. A little bonus AP at the start? I'll say hell yeah to that.

Feel free to comment and vote. PLEASE leave comments so that I may learn how to improve this guide. Negative comments believe it or not will be appreciated seeing as they (like positive comments or questions) will allow me to build a better guide. Do not down vote this guide without leaving a comment, that helps no one and ruins the possibility of other players finding something on this site. (Who goes to a guide for a champion when it's rated 50% as opposed to 80%? I certainly don't.)