Now before I begin, I noticed that my last guide and all guides, as a matter of fact, are attacked by trolls (even though the troll has terrible guides with around 50 words consisting of 'OP CHAMP RIOT NOOBS', I don't mind CONSTRUCTIVE criticise, I love it as a matter of fact and I take all thoughts & feedback into consideration, but please try out the guide and don't just look at it and say things like:
'Not enough ability power'
'To squishy'
'Useless noob don't start fights with karthus!'
'**** guide'

I would really prefer something like
'Not bad, I disagree with you item "Death cap", and getting it so early' - We are not monkeys people please use some brains and lets act like civilized players, looking for an competitive edge =)

"I have this desire to keep improving, so I find fault."
Heston Blumenthal


Not that my rage is over back to the guide. =)


Thanks for taking the time to read my guide giving me the honour of showing you how to play the rage master, karthus. Here is the history of this deadly champ.

The vast quantities of physical magic that were consumed and destroyed during Valoran's numerous Rune Wars have scarred much of Valoran. Many locations far from civilization have been morphed into hazardous and dangerous locales. The Howling Marsh is one of these places, and the self-appointed overlord of this land is the lich known as Karthus. It is thought that Karthus was a mage who, in life, was foolish enough to enter the fetid waters seeking his fortune, and that he was forever transformed by whatever dark magic permeates the swamp. Karthus now rules over his swampy dominion with an iron (albeit skeletal) fist. Visitors are not welcome, and those who are not scared away by the lich's terrible power most likely end up as one of the undead themselves... skeletons and zombies in Karthus' growing army of eternal servants. On the darkest of nights, Karthus is said to sing the tales of those who have succumbed to the swamp, past and present.
Karthus' tenure in the League of Legends is one of the more unusual ones in the history of the League. First, it is highly unusual that a lich who was known for isolation and hatred of life would even be a willing part of an organization which promoted the preservation of life. Next, Karthus specifically eschews the accrual of power and influence gained through service to the League; he is essentially an unpaid volunteer. This behavior is completely different than what his life outside of the League would have onlookers believe. Karthus has never spoken about his intentions in being a champion of the League, and in fact becomes quite agitated when asked about it. In the interests of not aggravating a lich, most sensible people subsequently drop the issue.
"Come visit my home, and I shall sing a dirge of your life as it once was."
Karthus

You will need the following
+ Good map awareness.
+ Decent teamworking skills
+ A mass amount of practise for landing skill shots.
+ Patience
+ Basic math and common sense for estimating damage of your ultimate.

Pros
+ Damage output start game is beaten by none.
+ Can farm like crazy the whole way through the game.
+ Great lane stability with your passive giving you your mana back.
+ Great damage the WHOLE way through the game.
+ Can get kills even from the grave.
+ And has a global ultimate that can damage all players on the map.

Cons
- Focused to an insane extent.
- Raped by CC effects(Stuns, fear etc.)
- Very little CC and has no natural escape mechanism.
- Mana problems early game if they are spammed to much.
- Needs alot of practice to get your spell position correctly.
- Is hard to against blink champs / champs that don't require to dedicate themselves in a fight,(ie Morgana in laning)

Before I actually go into my items, I feel I must explaining why I have chosen the items above. The reason I have chosen items that focus both on HP and AP is because I believe you can do ample damage to enemies with Karthus without being absolutely AP based, I find many Karthus players to think the more damage they can put out the better? I fight them one and one and they die in 3 - 5 bombs, it also gives these Karthus players the inability to use defile right, I can live for at least 6 seconds in any team fight I flash into to "Suicide". And an additional 8 seconds of life means I can do a hell of alot of damage.

In addition, I wont be focused as a squishy member of any team and will rarely die due to my mass hp and will be alot more to my team than a glass cannon that needs protecting and to go back for hp all the time.

As for my base item build, I will be explaining why I chose certain items and which items may be changed and in what situation must you be in before this happens.

First of all why did i start with

The answer is simple, Karthus relies heavily on his ability to land his skill shots, without a speed advantage or at least leveler you will have massive problems vs most if not all champs if the player has even a basic knowledge on how to avoid you skill shots, in addition, as you lack a real hard escape mechanism besides maybe this will help us get away from those start game ganks :).




Second Item

This will be the last item i will be explaining that is in the base build, the rest are pretty self explanatory. Now why rod? Simple, every level you will be getting mana and hp back allowing you to lane even longer as-well as the additional survivability, this item is perfect.
"If the world was perfect, it wouldn't be."
Yogi Berra

Third Item

The reason is simple i don't think this even needs exaplaining.

Fourth Item

Not a standard item on Karthus in any way, i have been flamed at for buying in a few rare cases but this item does work, every time you lane you Q they are slowed, hence you can land another Q and they will be an even easier target, this item is good to ensure no-one gets away and provides much needed CC and control in a team fight. In addition you ultimate will provide a slow, so if you ever die and you team are about to clean up, this will make their job childs play, or if they need to get away a nice slow works wonders.

Fifth Item

As nearly all games people will get some sort of magic resist or have large amounts or natural magic resist, we want to cut through this in a simple way that will provide more damage, thankfully this item will do just that.

Situational Items

Banshees viel if a great item on Karthus if the enemy team is very AP heavy. This will give more survivability as well as helping you do some damage to a team that has a large amount of CC.


Ok, this isn't in the item set above, BUT if you having a lot of trouble in your lane this will help you get back in the game with some quick hp/ability power.


Mejai is one of the most perfect items on karthus if I have ever seen one, most people will think "Its to risky" and "Hard to keep the stacks", but i'm here to ensure you that this is not the case with Karthus. I sometimes get it straight off the bat as most kill you will get will be very early, early game many people will be getting away by a small amount of health, this is where you come in and help them back to base, and give you 2 extra stacks. Again, mid game/late game even if you are suicidal, 5 assists for 1 death ? 5 stacks for maybe 3 being lost? The risk of this item being useless is little to none BUT if you are playing high ELO and are new to Karthus I advise not using it until you are confident you can use this item to the fullest extent.
"Risk comes from not knowing what you're doing."
Warren Buffett


For those people who would like to have the ability to stop a certain kind of cc without their banshee getting popped and being left vulnerable again you should get the QuickSilver Sash, this will allow you to remove all CC effects upon you every 105 seconds.


Many people laugh at getting armour on a Karthus, but if the enemy team is very AD heavy, why leave your weak to being allowed to get life stole upon or cleaned up? For a sexy 2k gold, make that Trnd think twice about focusing you.


Will of the ancients is the perfect item if a large portion of your team are AP based, the spell vamp will also help you lane aswell as giving you that much pack to your teams punch. Don't be selfish, getting items for all your team will help your team rise to greatness.


The reason i may change to these boots is if the enemy team are packing alot of magic resistance. This will help you deal the additional damage by cutting through there resist.


I sometimes get this if the enemy team is highly ad oriantated and my tank is doing a good job so I don't need my . The active of this ability allows you to remain invulnerable for 2 seconds, its very useful fighting high burst damage champs or in team fights if you are getting focused, and of course it could protect you from that enemy Karthus ultimate =)


Good item for those all-rounder team as the resistance's are great aswell as it's active when you die, As i've said before, Karthus is the reaper of death, nobody can kill him.
*Tip* While getting reborn your is still active and does damage to all enemies so you may still use your flash/"Suicide" tactic in team fights to an even greater extent.


Fantastic end game item for Karthus, it can be used to take towers with ease as your is very spam able. The additional damage also helps, not for me personally but if you like getting more in range than you have to go ahead it does works great if you are lacking a good carry taking towers.


This item can be used to kick the *** of those tanks and smart-***s getting warmogs, this gives you a passive 10 mana regain per 5 secs and 60 ability power aswell as a 15% cooldown reduction! Great huh? But this i'sent even the good apart, its active can be used to:
Deal magic damage to target champion equal to 30% of their current health (+3.5% per 100 Ability Power) with a miminum of 200 damage. And with only a 1 minute cooldown. Fantastic item!.


This elixir will increase your ability power by 20-40 depending on your level, if you are having a problem with having to little butter to your toast then i suggest getting this quick solution, it will increase all damage you deal, perfect just before a team fight giving you that small edge. Don't underestimate potions, they can be a great help.


Again, another great item to get the edge of that brief mid game squishiness, with my build you are not, but if you are having a small problem and just not getting away I suggest getting this item once until you are maxed.

"Any tool is a weapon if you hold it right."
Ani DiFranco

OK for how to play Karthus, i'm going to start with mastarys. Pretty basic 9 - 0 - 21 focusing on utility.

For runes I start of with full ability power, this will help provide that much needed pack to your punch for your start game farming and harassment.
Same for the glyph, more damage start game.
And alas the same yet again, we want as much ability power start game as possible.
And finally full maigic pen marks to allow your ultimate to hit its maximum start game as all enemies will have natural magic resist, we want to ignore this as much as possible to make maximum damage.

\\\Good spells to take///

Flash
Main reason for flash, its obvious if you have ever played him or you will find out when you do, he has basically no escape mechism meaning the only way he can get out of a gank is to throw his "Wall of pain" which gives a slow to any one person passing through this wall, the main problem with this is certain champs such as Yi and Olaf can simply run into this wall with no effect onto themselves and nuke you down in a matter of seconds, nice to have a way to bounce over a wall and escape the most deadly ganks. I will be explaining how to use this in another way later in the >>>> Game play section.


Teleport
This is a fantastic spell for karthus, I use it to ensure I lose no farm in my mid lane and can buy my mejai ASAP as well as solving my start game mana problems. Also the ability to ensure others towers can be protected or obtaining a potential gank is also useful.


Clairvoyance
Rarely see a karthus with this, but to me, it is an acceptable spell, you may use it to better assess an ultimate usage, time to look at the their hp, remember most players don't know what your ultimate can hit, so try and assess it yourself. It's really up to you if you miss alot of action on the map. In addition helping your team by checking dragon and baron is always useful.

______________________________________________________________________________________________

\\\Bad spells to take///


Clarity
OK, now for all of those *Sorry to say it* idiots getting clarity on a champ who DOESN'T NEED IT! If you are creeping correctly, you will not need this spell, only last hit creeps start game, you haven't got the mana to drop bombs like a terrorist. If you are having insane mana problems end rethink your farming tactic and try to last hit more often, in addition you may need to stop harassing your enemy in lane as this consumes mana that could be better spent farming.


Ignite
You don't need the additional damage. It is a good spell for say and first blood, but you could get a better spell, leave this for people who can't nuke someone behind a tower.


Exhaust
You aren't a melee and with your you CAN catch with with people, let the people with no cc at all get this.


Heal
I suppose it is usful early game but end ? Basicly you could use a better spell it isen't worth a whole slot taken.

Ok now for all of karthus's abilities and how to use them.
Death Defied

Karthus's passive allows him to defie death for 8 whole seconds. This leaves 8 seconds to drop your wall of pain, lay waste, toggle on defile or even use your ultimate.

*Tip READ* The reason this ability is so good, this is the simple fact that while being "Dead", all of your ability's cost you no mana! So you are free to spam and turn on ALL ability's !

Usage
+ To last hit an ememy on low hp scoring you the kill.
+ To use your ultimate to kill or ingure all enemies.
+ To change the tides in a team fight
+ To potentially suicide into a team fight and let yourself be consumed by the ultimates that follow, this is fine when it happens you die in the middle and you have 8 seconds to reek havoc while they cant harm you at all, this can either force the team to disperse therefore allowing your team to clean up some kills OR they will continure fighting on you, which will lead to their death.
+Remember to drop a in the middle of the team to help your team mates pick of the kills, wait for your death to do this.
______________________________________________________________________________________________

Ok now for karthus's bread and butter, "Lay waste" This ability lets you drop an AOE bomb that will do damage to all surrounding enemies. This can cause massive damage all game and is great for poking all players with, this skill may take players 20 - 30 games to perfect your bomb placement. So your first game with karthus and your doing bad? Don't worry this ability is key to your success but it takes practise.

Tips for bomb placement
+Try to single out an enemy, it will do an amazing double damage if it only strikes 1 target.
+Place bombs beside or behind targets based on their previous movement patterns ie they tend to just run back, place behind them.
+ If the enemy is moving around giving no chance of success,don't even harass them at all and start farming, pretend they aren't there and place the perfect single target bomb at them every 30 seconds, this will ensure they don't try and move you in lane AND you don't have to waste all your mana attempting to hit a target going around like a plastic bag behind Tesco's.
+ Place a bomb in a suspicious bush to have it revelled with allot of damage to that sneaky C!@t hiding in it.

Things not to do
- Do NOT spend all your time and mana trying to harass, only do when possible, to many karthus's seem to think the more the merry, but remember this, warfare is based around percison, if you have it use it.
- Do NOT spam in between minions every wave, this will ensure you have so many mana problems that harassing will be out of the question, use your bombs on single target minions or groups of 2 with a small amount of hp, dont lower their hp with random bombs hitting multiple targets. This will not grant you the extra damage bonus from landing a bomb on one target.
______________________________________________________________________________________________
Me - Wall of pain is a wall, that is made of pain.
You - Wtf serious?

OK I joke I joke.

Wall of pain is passable wall between 2 obelisks at target position of your choice. Any enemy passing this wall have their armor, magic resistance, and movement speed reduced for 5 seconds. The wall lasts 7 seconds. This spell is largely under used by many karthus players. This spell can help slow your emenemy or groups of enemies from running or attacking.

Uses
+ The obvoius one previously mentioned is the ability to slow an enemy running away.
+ Again mentioned before, saving a fleeing enemy or yourself from death.
+ In the middle of a team fight lower resistances and mobility of all enemy players.
+ Check bushes as it will light the whole way along your wall.
+ On minions to slow the wave down and lower there magic resist.

+ There are countless ways to use this, in a team fight if you thrown down your you create a physical barrier in your enemys mind, they see no way out, so this ability alone can cut a team in half and force the other half to run away. Remember this is all about physiologically and out witting your enemy, this spell is fantastic for demoralizing an enemy and making them feel 'Singled out', panic and run away. Leaving you time to pick them off 1 by 1.

+ If your at a tower being attacked by 3 - 5 people, usally for most champs they will just throw you away from the tower forcing you to run, f@*k that, with karthus this dosen't need to happen. In the mind of your enemy they will see the tower as a small threat, and you as a minor one, but once you throw a pointless wall in front of them, they will think twice about about attacking you, put on defile and throw bombs from behind it, you can save 9/10 towers from destruction because of this, mentally you enemies will be to scared to attack, even though they could easily kill you at the tower. To many thinks going on at once will confuse your enemies. Remember the human mind can only comprehend around 5 things at any one time in a simple snap decision.
(Ever tried to remember more than 5 numbers at once? It can be slightly harder for some, That is why pin numbers are even and 4, we have an easier time remembering even numbers, cool huh?)

What not to do with the wall
- Use it to 'Slow the dragon/baron' This dosen't work don't try it sigh.
- Threw walls, this dosent work either.
______________________________________________________________________________________________

Defile is an aoe damaging effect that will harm all enemies inside for every second they are in the aoe. This ability has a toggle on and off effect as well as a passive, i will be explaining both.

Toggle on - Toggle on, as said before will create an aoe circle of 550 around karthus that will damage all enemies inside it.
*Tip* Rylai Scepter works with this, on other words your enemy will be slowed down while in your circle of death, its the reason it is in this build, it can help you get away by slowing an enemy behind you if your wall is on cool down.

This will do -
Magic Damage:
Level 1 damage: 30
Level 2 damage: 50
Level 3 damage: 70
Level 4 damage: 90
Level 5 damage: 110
+0.25 per ability power point.

---

There is a downside to this amazing damage, the mana cost which IS substantial.
Cost of defile at Level 1: 30
Cost of defile at Level 2: 42
Cost of defile at Level 3: 54
Cost of defile at Level 4: 66
Cost of defile at Level 5: 78
*Mana per second*

How to use the toggle part of this ability
+ To farm minions, this spell is easiliy one of the best farming abilities in the game! Use to kill mass amounts of minions with ease, do not do this at an early level as the mana cost is far to much!
+ Pretty basic and the base use of this skill, to do additional damage on an enemy.
+ To scare enemies, i know this sounds stupid but a big spinning ring around a person throwing bombs around to many is scary.
+ The main use of this ability! As you know, karthus can live 8 seconds after death, so a suicide attack with death and this toggled on can cause ALOT of damage and pick you up plenty of kills, I have mentioned this before but I believe this is extremely useful in any team fight.

How not to use the toggle part of this ability
- As mentioned before, but i feel that i really should ensure people get this into your heads, not to be used to farm every last single wave of minions until you are at least level 12 + or extremely fed having mass ability power. Your bombs are better start game at this so don't worry.
- While trying to catch an enemy, remember to turn it off before the real fight starts of you will find yourself out of mana very quickly.

---

Passive of this ability
The passive of defile provides you with mana restoration for every kill you receive (Applies to minions as-well). This passive is the reason you DONT need clarity or any mana items. Depending on the level you will recieve mana back from your bombs, this is why i prioritise AP over mana items, once you AP is high enough and you are killing sets of 3 minions with 3 bombs you will be gaining more mana than you used. Many people believe this leave karthus unsustainable early game due to mana problems, this to me is incorrect, just concentrate on last hitting minions to get your mana back or at least as high as possible and don't spam on massive waves of minions and your mana pool should be fine. Once you reach level 8 or so these mana problems completely disappear so I think it is worth holding back abit start game for the return of a mass amount of quick AP mid to late game.

Mana Restored with defile at level 1: 20
Mana Restored with defile at level 2: 27
Mana Restored with defile at level 3: 34
Mana Restored with defile at level 4: 41
Mana Restored with defile at level 5: 48
*Per kill*


*Before we being*
Karthus's ultimate is widely known when applied to a notorious sense among the Lol community, the common rule that his ultimate is a 'Cheap shot' to me is unjustified and unfair to any karthus player who will be constantly reminded that this ability is 'Noob'. Now for all of those who believe this is true, i will say one thing, it is a good ability but not OP, the reason for this is that their are countless ways to avoid the fate of his ultimate and the fact I dont hear those players complaing when their
/ / / / / / / / / / / / / / / / / / / / / / / / / / / / / ...

Pop their ultimate on me and in quick succesion own me big time, or when that same trnd hits me 1k damage late game in 1 strike. Please don't criticize karthus's or believe if you are playing him you are a "noob", this ultimate is as good as anyone else's and is only OP (as anyone else's usually is) when he is/she fed.

---

Karthus Ultimate is called Requiem and all allows Karthus to deal magic damage to all enemy champs on the map. This requires a 3 second channelling period.

Magic Damage with Requiem at level 1: 250
Magic Damage with Requiem at level 2: 400
Magic Damage with Requiem at level 3: 550

Uses
+ The base use of this attack is the ability to kill any escaping enemy in your lane with low hp.
+ To kill other enemies in other lanes on low hp.
+ To help a small team fight in a other lane.
+ To change the odds in a teamfight. This ultimate can literally turn a teamfight around! The best use of this ultiamate isent just to "finish people off". This to me is a waste of an ultimate with a large cooldown, No the best way is to use your ultimate just before a teamfight, as soon as your tank engages pop your ultimate to lower the hp of all enemey champs giving your team a large agvantage over the enemy.
+ As previous point said, you may also flash into the middle of your enemies to start of a team fight and pop your ultimate when you have died giving a mass advantage to your team, remember to place a wall just before you die!
+ A largely un-used use of this ultimate is to make attackers chasing a target to retreat, as i've mentioned, this game is all about out smarting your enemy, Nobody likes to see 1/4 of their hp gone while chasing anyone.
*Only use previous point if the chasers have lowish hp and are chasing at least 2 people*

Things to do with your ultimate
- DO NOT STEAL KILLS OF YOUR TEAM-MATES!!!!!!!!!

"Desperation is like stealing from the Mafia: you stand a good chance of attracting the wrong attention."
Douglas Horton

- Do not use it unless you have a good chance of killing your target, contrary to popular believe karthus's ultimate dosent take over 2 bars at the start of the game.
- Dont always beleive allied members of your team, if they call for your ultimate, check if you can the hp of the enemy they are talking about.
*Avoid previous point if you are playing with people you know who have a fair idea what your ultimate can hit.

Important things to considor when applied to your ultimate
+ Easy first blood? By the time you are level 6, most junglers in the enemy team are just about to go back, Pop your ultimate as soon as your level 6 for a easy kill, I have around a 70% success rate =)
*Previous point - Dont try on Warwick, his lifesteal is to great.*
+ Your ultimate can be stopped from any fear, stun or taunt, so be careful when you use it or who you use it around.

+ Give yourself a fair portion of success when readying an ultimate, here is the calculation i use.
>Current damage of ultimate
>> Check magic resist and take it away from damage
>>> Take away end damage from enemies current hp.
>>>> Use/Dont use ultimate

*Tip* Check for banshees and the hourglass when ever looking for an ultimate use, they will stop you completely.

Red - Big problem
Orange - Moderate problem
Green - No problem as long as a red i'sent around them.

Characters to watch out for before doing your ultimate
Janna - She has a shield and ultimate that could save her or multiple targets.
Karma - She has a shield and ultimate that could save her/target
Kayle - Has a heal & ultimate that could save her/target as well as a heal that could potentially save 2 people.
Lux - Has a minior shield, dont worry about it to much, but start game it can completely offput your ultimate.
Morgana - Has a good shield that can save one person from nearly any damage from your ultimate.
Nidalee - Heal can save target.
Shen - Shield can save target.
Sona - Heal can save target.
Soraka - She makes me want to commit suicide, heal can save single target and ultimate can save a whole bunch of them! Cost me a penta kill once. 13itch "\0.0/"
Zilean - Can cast an ultimate that will bring target back to life.
Taric - Heal can save single target.
Orianna - She can provide a shield to one target protecting them.
Alistar - An AP alister can heal and save multiable targets.
Galio - Can improve the magic resist of one target and save them.

Single targets who are less danagerous but can save themselves
Rumble - Rumble can activate a small shield saving him some damage.
Sion - Again, a shield may be activated to reflect damage.
Annie - Largely underestimated, she can product a shield that gives her a very small amount of magic resist that could save her *Rare*
Anivia - Alas, this bird turns into a egg and is reborn, completely saved from your ultimate. If you ever ultimate on her make sure her egg is on cooldown!
Warwick - Even if he is on 100 hp late game he can life steal like a mad man, make sure he is away from creeps to ensure success.
Xin Zhao - A small amount of passive lifesteal, is alot early game when you considering 40 hp is the differnce between a kill and no kill.
Rammus - Can activate an ability that will increase his magic resist.
Nasus - An ultimate i nearly always forget, it gives him "x" amount of additional hp making it hard to know when to use your ultimate on him.
Vladimir - Little rat, he can life steal, or pool to get away from your ultimate, very hard to kill i can tell you that. Try to get him on all of his cooldowns away from creeps. I usually wall to make him pool then ultimate if i can.
Shaco - Believe it or not, if shaco pulls his ultimate he can take no damage from your ultimate.
Dr.MundoDr.Mundo - His ultimate can give him insane life regain, be careful when considoring using an ultimate on him.
Malphite - Has a passive that gives him a small shield if he is out of combat a certain time, it can save him alot of damage start game.
Leona - Has an ability that can increase her magic resist.
Udyr - Udyr can activate a weak shield to deflect some damage.
Sivir - Annoying, Has an ability to protect her from 1 enemy spell, saves her all the time, the cooldown is small aswell, get her with no mana if you can.
Jarvan - Can product a small shield, nothing massive but start game can be considerable.
Fiddlesticks - Pretty obvious, he can life style mad. Get him running away from minions and he is dead =)
Urgot - Can create a small shield.
Tryndamere - Yeh well, what can i say ? Has a massive heal, can get himself massive life steal, has an ultimate ensuring he has no chance of death. Not Op at all... -.-
Nocturne - Same as Sivir, has an ability to ignore one enemy spell.
Nunu - Can eat like prawn! He gains ALOT of hp from this. Make sure he is away from minions before you pop that ultimate.
Poppy - Can put her ultimate on an enemy champ from behind a tower or in the middle of a fight to only allow them to damage her, Basicly you can touch her while she has this 'Golden circle' around her, wait until it is gone and pop.
Mordekaiser - His shield can completely save his ***, although he has to pay in HP to use the ability, make sure he is away from minions.
Master Yi - Meditate can save his ***, magic resist and hp regain? Pretty hard to beat, most Yi's will forget this so I usually risk it any-ways.
GankPlankGankPlank - Can eat his, well I duno ? And give himself some hp back.
Blitzcrank - Largely forgotten skill, when he is under 10% I believe? he gains a shield that goes of his mana. It is usually pretty good and don't underestimate it, wait until the shield goes and use your ultimate if possible.
Green
This pretty much is made up of every other champ in the game, who, if a red isn't around is, well their is only one way to put it, screwed?

*Tip*
There are a massive amount of factors to be considered when playing Karthus, many think that you just click your ultimate and smile, no from now on you will consider all possibilities. Most of these factors will sometimes not even effect you, mid game sometimes nobody can save your target(s).

"Think before you act and act on what you believe."
Bo Bennett

Now i have went over all the simple stuff with Karthus im going more indepth on how to play this champ other than how to use his abilities.

First off is karthus's ability to creep with the best of them all times in the game.

Start game
Be careful start game with your mana, try and focus on creeping as much as possible, remember if you hit a single target with your bomb, it will do double damage, so a single boss creep sitting out in the open with 1/5 hp is perfect for your free income =). Try and get the hang of how much damage you do to 2 targets and how much you do to 1, 3 etc. This will help you creep alot better. If you have no jungler, try and get someone to help you get blue pill.
*Note* If there are a wave of creeps coming they always bundle together making it hard to create that 'single bomb effect', but not impossible to do this you must first pick of the side minions, drop a bomb just outside the wave but close enough to the minion you wish to kill, this will allow a 2 bomb easy kill in most cases.

"Be precise. A lack of precision is dangerous when the margin of error is small."
Donald Rumsfeld

Mid game
Now your mana problems should be disappearing you have the ability to start spamming your bombs on minions with confidence of getting all your mana back. Use this to your advantage eat up minions and be aggressive in your lane. Try and get the blue pill if you are having small problems with mana, also a cool down on your ability's always helps.

"Action makes more fortune than caution."
Charlotte Whitton

End game
Use defile to cut through minion waves as-well as the odd bomb, your mana problems will be completely gone and you may spam out. My suggestion is to leave blue pill to a more mana/cool down dependant caster in your team such as lux, le blanc, Annie, brand etc, don't be greedy!

"Greed is the inventor of injustice as well as the current enforcer."
Julian Casablancas

Green = Easy Kill
Orange = Potentially difficult
Red = Hard

These are all potential match ups, some may not be that likely but all can possibly mid lane.
Leblanc - This girl is very difficult, play safe and just farm, remember her blink can nuke you down, stay behind your creeps.
Teemo - This little guy never had a chance, harass and keep him on his toes, denie as much minions as possible and enjoy the free farming
Ashe - Can be difficult, avoid her volley and keep her dancing, be wary at level 6 she can stun and kill you.
Akali - Simple until 6 when she will reck you, denie her start game farm.
Ahri - Avoid her skill shots and you will be fine, just keep on your toes and ensure she does the same.
Fizz - This guy is pretty annoying you can't lock him down as he can run through minions making it impossible to lane a single Q on him.
Diana - I'm updating this when she was first released, she recks you badly harass until 6, i'm just gonna hope for a nerf =)
Sion - Hard, he can negate damage with his shield and then stun/shield you, when you see him shield stay out of his way.
Master Yi - Ap yi is actually pretty annoying start game, don't even bother harassing just out farm him.
Pantheon - THIS GUY WILL **** ON YOU, he recks you so badly but stay WAAAYYYY back and farm.
Janna - Not a hard lane, but she is annoying don't do any trade offs as her shield will save her, just try and keep your wave from reaching the tower and stay out of the way of those winds =) She can blow pretty hard ^.^
Zyra - Can be difficult if you cant avoid her skill shots, she has mass bursting damage and can farm at a distance, you can out harass her if you can read her movements, start game she is weaker than you so take advantage of this.[/color]
Viktor- This guy out harasses you due his shield and he can farm at insane distances, he has a stun that can put you back big time and he can out burst you, just farm and play safe.
Galio - This guy is next to impossible to kill mid/late game and his damage in the start/mid game is ridiculous, BUT his start game is plagued with mana problems, try and get him start game, if you can't i'm sorry but its another farm lane.
Talon - He countered you hard style, if he knows how to play you will rarely land any sort of damage on him, he can silence and burst 1/3 of your hp at once, he is a problem and a very difficult lane, stay wayyy back so he will draw minion aggro start game, slow him to ensure your minions do some damage and try and lane some Q's.
Xerath - Rare champ to see, but when you do he will have you running for the hills and sniping you from his base. He is an extremely good champ with more range than you, a stun and a level 6 that will in one burst sequence kill you automatically, just MOVE MOVE and MOVE a little more, keep on you toes and try and stop him pushing you under your tower where he can snipe from blacked areas.
-Ziggs - If you can avoid his skill shots you will do fine, he is hard to harass due to his range and escape abilities. Just try and farm and beat him in the end game when he is a little less effective.
Caitlyn - Very difficult to be against, alot more range and damage and you have, play very very safe and JUST FARM don't even try and harass her.
Zilean - Can be difficult, massive damage start game but just keep your distance and harass him.
Karthus - Mirror match can be hard if the other Karthus has more skill/games. Farm and harass as much as possible. Evaluate your situation if you think you are better or not and match it with being more/less aggressive in lane.
Lux - Can be difficult, just avoid her skill shots and you will be fine. Your damage is alot higher than hers.
Mordekaiser - Who da f@!k made this champ ? Harass when he has his shield down and just farm away.
Katarina - Depends completely of skill level of the Kat, avoid her dagger throws by keeping to the left/right of minion wave. Harass her as much as possible until level 6 where she will try to out, just flash our of it and continue to harass her.
Swain - This guy completely relies on his skill shots, don't get caught by his snare or you will be forced back to port, avoid this and you should be able to out harass him, you can also out farm this guy greatly force him back to tower to limit his mana regain ability of his passive.
Lee sin - Can be tricky, dont underestimate this guy with his so called "Limited range" He CAN and WILL nuke you down if he lands his . This will mark you and let him get in close to do massive damage, it will also make it hard for you to hit him with your .
Kassadin - Very easy to lane against start game, Harass massively until 6 when he is destroy your soul, ask for ganks and grab some sort of magic resist vs this guy.
Brand - A hard enemy indeed, keep clear of his skill shots, he will beat you start game without a problem, simply out farm him.
Anivia - Very Very hard to lane against, you have to kill the 13itch twice and you simply dont have that kind of damage start game, once she reaches level 6 start clear, until then harass and annoying her as much as possible while farming.
Fiddlesticks - Has the potential to be impossible to lane against, depending on their skill level, try and harass a small amount but if he is just draining up just focus on your farm and avoid his .
Corki - Little guys plane will go on fire will the harass you can throw at him until level 6, once he reachs it his harass game is crazy, keep on the move and farm.
Ezreal - His blink can kill your champs of trying to get him with but otherwise if you can avoid his skill shots he is an easy kill.
Vayne- Very hard to lane against, play defensive completely with a small amount of harass if she singles herself out.
Morgana - Very easy to lane against, avoid her stun, bingo she is dead.
Orianna - Another hard enemy, she has alot more range than you but you can farm a hell of allot better so don't worry, play semi aggressive with her.
Sivir - Could be difficult to defeat if you cant avoid some of her techniques.
Tristana - Very hard to lane agaist due to range and damage output, as well as the ability to jump near you, farm and keep your distance.
Twisted Fate - Little bugger is very squishy start game, with my build start game 4 single bombs kill him. Haras while farming.
Vladimir - Start game this guy makes me think he has AIDS or something, nuke him back start game, when he hits 6 and starts grining you down be careful! Keep distance and farm.
Twitch - Very easy to lane agaist, when he attacks WallOfPain and bomb.
Veigar - Can be very difficult, his ultimate can reck you end game, you can beat him in lane though, play aggressive and outfarm him.
Urgot - I need a knife playing this guy, he is such a melt start game i could cry, avoid his shots as much as you can and just farm, without kills this guy fails hard.
Malzahar - You can outlane until 6, then he owns your *** buddy. Farm until then and just keep it safeish.
Kog'Maw - Start game it is pretty easy to beat him, he i'sent really a problem until late game when he out ranges you hard, harass and farm.
Annie - Simple until level 6 when she owns you with tibbers, counter with flash if you can, be semi aggressive but keep out of her stun radius.
Heimerdinger - Ignore turrets and farm, he cant really be killed in mid unless you get lucky with your harass of him, mainly farm and don't attack the turrets.
Kennen - Very hard to Lane against, he spins around like mad and throws his little f@!king starts. Harass till level 6 and start playing careful, his ultimate can mess you up.
Ryze - This guy can grind and burst you down with ease, very hard to lane against. Farm and keep your distance.
Cassiopeia - Avoid her skill shots and you will be fine, you out damage her massive aswell as out farm.
Gragas - Easy champ to be against, avoid barrels and harass him like mad, the fat man has trouble avoiding them, like how can you miss? Am i right ?
Miss Fortune - Moderate to lane against, just don't get caught slugging it out with her, harass and slowly grind that HO down.

*Refer to color codes on champs above and play against accordingly*

Greens - How to defeat / play against

When i said harass i mean any time you get a chance throw down your and don't worry about the repercussions. To harass simply stand behind your minions and as said before drop until your enemy stands going back to his tower and playing defensive. If he decides he can take it "And oh he will" wait until he is around half hp and drop your directly on him lowering his magic resist and forcing him to take the most direct path to his tower, put lay waste directly in front of him and if needed finish him of with your ultimate. This nearly always work as start game 3 single bombs from Karthus hurt any champ regardless of how beefy they are.

"Anticipate the difficult by managing the easy."
Lao Tzu

Oranges - How to defeat / play against

To play against the oranges you must be semi aggressive, they guys have a chance of killing you but if you are good enough they shouldn't be a problem. Anytime they are out in the open try and get your Lay on them, but don't over extend and try to get as much farming as possible done, while that small amount of harass is in their, remember if you have a chance of them in the open, Take it! Use your on them and finish with and your Ultimate, even if this doesn't kill them you must send them back if you can.

"Nobody ever drowned in his own sweat."
Ann Landers

Reds - How to defeat / play against

For the reds, play safe, they will almost always outlane you with damage and or farm, just concentrate on your farm and avoid their abilities, but remember, being a ***** won't get you anywhere, if they start getting cocky in the open, make them pay for it with 2 or 3 and retreat, you don't want them to have free farm, playing safe means don't take any risks, only attack if you have a wave behind you and they are in the open with no way of catching up. If you are facing reds while farming look for some kills with your ultimate in other lanes as you will most likely not get stacks of any red. Even an assist start game will help you alot. Don't panic against the reds they are beatable if a 'Noob' is playing them or becomes cocky and get caught in the open.
*Tip* If against a red, ensure your jungler (if you have one) or other lane mates know that the enemy in your lane is top priority for a gank! Them getting killed will pull in their reins and not f@!k with you anymore.

"I ask not for a lighter burden, but for broader shoulders."
Jewish Proverb

I see many Karthus players working as a sort of one man army kinda thing, i don't like it, you don't have to get every kill to be great, help your team out as much as possible, being selfish wont get you anywhere except maybe a 1 v 5 gank. This goes for any champ and every player, go with your team to ensure ganks are pulled of successfully and all towers stay secure. Also ask team-mates in other lanes if they would like your ultimate to help a small fight they are about to start, the extra damage is always a nice support for your team-mates. And call your (SS,MIA,GONE,Missing) please, ensure you are not creditable for any deaths in your team, ping if they seem to not be reading the chat.

Pretty basic stuff just always needs to be taken into consideration when ever playing any game.

"Teamwork is the ability to work as a group toward a common vision, even if that vision becomes extremely blurry."
Author Unknown

When ganking another lane with Karthus, you must first start off with:

Wall of pain onto the path your enemy will most likly run. Follow up with and walking into your enemy while dropping Lay waste everywhere. Repeat laying waste until the enemy is dead, IF they by so happen get away with say 100 hp simply ultimate picking up the kill.

In a public match, ill be honest, it's hard to find people playing support putting wards on the map, if no-body is, YOU SHOULD. I know this is meant to be the support/tanks job but what's 150 gold to ward both sides of your map so you cant be ganked by the jungler, if you have spare cash any time in the game, invest it into wards, it will get your team kills and leave the other team with the inability to gank you and all your team mates. Its your role aswell as all others to discuss who is buying the wards or deciding that it will be a team effort!

Wards win games, they can:
Give map visibility on key pointers in the game EG Dragon attempt/ Baron, where the enemy may be low on hp leaving you the time to strike and pick up those 5 kills for your team and the buff/gold.
+Counter gank some-one looking to jump your lane, cut them off with a ping from your team and their is a free kill.
+People getting away with the skin of their teeth? I can see you! You don't always need a twisted fate to find people running around in junlge, a well placed ward can tell you exactly where they are.
+A well placed ward in the enemy's base if deep in there jungle or lane can allow you to teleport to them and cut certain people off or back-door your enemies, don't underestimate this method ive gotten countless kill because of it.


Play Video
This isen't my video but I think it explains perfectly where to put wards and is hopefully helpful to you.
"Evil hiding among us is an ancient theme."
John Carpenter

Thanks for taking the time to read my build, I hope i have clairfied any misguided thoughts you have had on Karthus or any confusion you have had playing him =)

Just remember that Karthus is not only used for his ultimate, he can be used to kill almost anyone.

Peace out guys have fun playing this fantastic champ.

"I don't know the key to success, but the key to failure is trying to please everybody."
Bill Cosby

16/September/2011 - Guide Posted
19/September/2011 - 'Ganking' section added.
21/September/2011 - Some minor mistakes brushed up.
26/September/2011 - Added some more people to the 'People you may lane against'
01/December/2011 - Fixed some minor grammatical errors and other minor things.
20/August/2012 - Changed items alot, replaced staring item Doran's ring with boots, removed Mejai from 'Main item build' added a TON of champs to 'who you may lane against'. Changed my thought process on what i choice my items.
25/August/2012 - Changed description on my Q and how it works.
26/August/2012 - Changed the title, so it does more with what i'm trying to go for in this build which is an alternative way to play Karthus.