Karthus/Strategy

Skill usage

 * Sometimes it can benefit to die a strategic death, by rushing into a group of enemies and casting  the enemy will focus you long enough for your team to initiate without affecting your chance of winning a team fight, as  can cast his spells even after dying.
 * You can also activate right before dying to let  tick even longer.
 * His passive allows him to cast spells while dead. Abuse this every time you die and punish any who remain near your corpse, casting if not already used and endlessly casting . This may actually get you a kill.
 * When focusing on harassment, try placing where it will hit the champion, but not the minions. This way, it will deal double damage.
 * is a great harasser. Use your to zone your enemies.
 * can be used to scout brushes since it reveals a small area around where it is cast. Since the skill has a low base cost, this can be used to scout brushes frequently.
 * is very strong at farming minions and harassing enemy champions.
 * Taking 1 level of gives you a slow allowing you more time to cast  on fleeing enemies, as well as deterring attempts of harassment, even at their towers. In later game it is useful in team fights, thanks to its magic resistance debuffs. With this spell,  can actually be a very good ganker, as it slows and allows his teammates to deal more damage.
 * at higher levels can mow down creeps by standing next to them or walking past them for just 2 seconds. If given free rein or adequate protection from enemy champions, this can turn the tide of a battle very quickly or cement a team’s victory.
 * Ask your allies to help point out when you should use to get kills in different lanes, or alternatively, alert your teammates when you are about to use it. However, be sure to keep your eye out for action elsewhere on the map; you may be able to help someone when they otherwise wouldn't have time to type for help.
 * Before using to kill a retreating enemy, consider the shield/heal/defensive abilities and items of the enemy team; at endgame, it is usually more important to have an ultimate up than to force enemies to heal.
 * During laning, it may be more beneficial to attack the caster minions in the back and to kill them than to harass an opponent. If you find yourself being out-laned by the enemy, pushing them back and stacking up on your own minions can help control them and keep them away from your tower.
 * If your team can effectively distract the enemy, can actually be a very effective pusher, as the sheer speed at which he can consistently clear minion waves allows him to push his team's minions to a tower and destroy it in a short amount of time.
 * highly benefits from the buff, giving him increased mana regeneration and reduced cooldowns for all his spells, allowing a focused AP build.
 * can be used mid-game before a major offensive is launched to weaken all enemies, making them easier to kill.
 * and are useful summoner spells, as  often needs mobility in order to be an asset to the team.
 * It is possible to jungle using with the proper runes and/or masteries. To get the blue golem rune, use  only on the blue golem (missing the smaller monsters). This way, you will deal double damage to only the golem.
 * Be careful of when to use due to your ability power and the enemies magic resistance.
 * Both slow and stat reduction go through.
 * can be a viable tool to saving an ally champion's life due to its movement speed reduction. Use it to give your allies a chance to get away if they are running from a pursuing champion.
 * Notice that is very good at medium range, however he is easily countered by champions who can attack him from a very long range like, for example,.
 * Casting while actually alive is generally a bad idea, unless you are well away from any enemy champions or they are on the retreat from your team. You will become the focus of enemy champions during the lengthy channel, and if you die or are disabled during it, the ability is cancelled and goes on cooldown. If you die before using, however, you can still use it during  and your opponents will be unable to stop you in any way.
 * can possibly proxy if you build all mana due to his

Dominion and Twisted Treeline

 * is very good at interrupting captures via and.
 * On Dominion, can work as a potent defender in bottom lane (between the Boneyard and Quarry), thanks to his potent zoning, ability to easily defend his point until reinforcements can arrive via his passive, damage aura via, and  poke, and ability to have a global presence via . However, he is very vulnerable to ganks if overextended.
 * If you're taking as a top laner on Dominion (between the Drill and Refinery),  can prove quite useful as an initiation tool for turret teamfights (especially at the Windmill), as it increases the damage all your allies deal while slowing the enemy. (If placed right, it can even reveal their brush!) By taking levels at 3, 4, 10, and the remaining two between levels 11-18, you can become frightfully efficient at helping your allies cap points. As such, taking  to further improve your initiation can prove valuable.

Build usage

 * Due to, the enemy team will likely build some magic resistance. Building magic penetration items such as will help pass through their defenses.
 * can enable you to regain health quickly with or, especially with enemy minions around.  also gains full spell vamp when only used to attack a single enemy.
 * When played as more tanky build, consider as a top-priority item. Its passive provides slow for all your spells, but especially for, which you can use to kite enemy with terrifying efficiency.
 * On either lane for Dominion, has a great deal of utility. Not only can it be used to secure kills, but it can also slow via , butter up enemies for your teammates from afar, or simply work as a global capture interrupter.
 * Try building tanky on Karthus as you will try to stay in the teamfight with your on and spam.
 * Luden's Echo is terrifying with Karthus; the low cooldown on Lay Waste allows Karthus to proc Luden's ridiculously frequently, and the bonus 100 AP and 10% movement speed helps even more.
 * Building an is a strong choice for Karthus as  can quickly build up the Archangel's staff's passive.
 * On other hand, a will make Karthus tankier, while taking less time to reach its full benefits. You can get both if you are constantly OOM.
 * has nice synergy with . You can lower the target's magic resistance by 15% after ignoring 35% of it, ending up in 44.75% penetration when combined.
 * Due to his ability to rapidly spam his Q a Luden's Echo is a good purchase on him.


 * Since the now provides percentual magic resistance reduction, it can no longer decrease it below zero. Flat reduction from  has less synergy, but it can still be useful against champs with lower magic resistance.
 * As mentioned previously, Karthus can be played as suicide initiator. Build him fully offensive with items such as and  to maximize your damage output.
 * has great synergy with Karthus, especially after the buffs to its AP amount. Because Karthus has a lot of sustained damage, he has a very easy time procing the passive, allowing him to consistently wear down the enemy team, no matter how high their health pools are. Activate and proceed to shred the entire enemy team's health.
 * The magic penetration also has great synergy with Karthus during the early game, due to the high base damage on his ultimate.


 * is not a recommended item because Karthus is not only in risk of dying most of time due to his moderate range and his squishiness, but also because he wants to die anyway during teamfights, allowing him to spam his spells for free. Also, this is an item that is oriented for early/mid game snowball champions, but Karthus is a late game champion and it is very unlikely that he will be able to snowball early game. Also, he doesn't have great AP ratios and will not actually benefit that much from a fully stacked Mejai's Soulstealer (except for the cooldown reduction). Not to mention, this item delays the rest of his core items.

Countering

 * Playing against can be extremely frustrating, as avoiding death with a small amount of health left is nearly impossible due his . If you find yourself having trouble with an enemy, buying a  can offer at least some protection to his ultimate. If you are a caster and wish different/more protection, grabbing a  earlier than you normally would can save you on many occasions. If you are an AD-based champion and wish for some additional protection, a  or  can block 250 or 400 magic damage respectively from his ultimate if he takes you below 30% health. Beware however, those items aren't as reliable as.
 * Always remember, especially during team fights, that can continue to cast spells while he's dead without the cost of mana. When engaging his team, kill  first, then retreat out of his attack area before continuing the fight.
 * When in the midst of a team fight, it may be difficult to notice the attack animation of his . Be wary of this if you are playing a squishy character and/or have little magic resistance, as damage output is steady and deadly.
 * Also, do not underestimate the tick on his . It is DoT, so it may not be noticeable at first, but its damage can be as much as 160 per second, not counting resistances, on top of his damage from.
 * Do not underestimate 1v1 potential. He may be squishy, but his killing power vastly increases when fighting stationary, single targets. If you engage him as ranged, try to stay out of his  and keep moving to avoid his . If you need to remain stationary, stay near other targets that will be damaged by his  (e.g.: Allied minions or neutral monsters) to reduce his damage output. If you engage him as melee, you should either only do so if you have the level advantage or survivability to engage him in his AoE spells and live.
 * reduces magic resistance, instead of penetrating it. This means that damage done to you by all enemies will be increased. Keep this in mind while standing in or walking through his during a team fight.
 * Some players will intentionally walk into a teamfight and die, This is rather a great strategy if  is in a situation where he will die because he can cast his spells for 7 seconds after his death. Make sure that after you kill him, stay away from his.
 * Do not ignore  upon killing him. Due to his passive, he can cast any and all spells freely, with the only restriction being cooldowns. Ignoring this fact and staying in close proximity to  before his passive wears off can often lead to him killing you.
 * Laning against can be challenging if you are not aware of his . Without at least one movement speed increasing item (e.g. ) walking away from your minions can be costly even while watching for  if the  is predicting your movements accurately. To avoid the doubled damage, stand near one or two minions. That way, if  attempts to harass you with, he is either doing minimal damage to you and the minion or placing it so that you have more time to respond, as the AoE is only half as close to you. Standing in the middle of your minions is a less favorable way to reduce damage as the unit collision can more or less hold you in place while  can cast s continually.


 * is known as the ultimate, albeit an indirect counter to, as she can use to completely counter , by healing the low-health teammate that would be killed by the ability. Even if she does not have Wish available, if Soraka is nearby the low-health teammate, she can heal him using  so that he is not killed.
 * Be wary that unless Soraka builds some AP, can potentially outdamage  late game, and kill the target even if he is healed.
 * In general, champions who have heals and shields can prevent themselves or their teammates from being killed by . Examples include and
 * is a good counter to because he deals more damage to an isolated Karthus using  than he takes damage from  while isolated. Kha'Zix also has too much mobility to be consistently hit by Lay Waste. After killing Karthus, Kha'Zix can just jump away using  so that he doesn't need to take too much damage from

List of champions who can potentially avoid being killed by

 * Any champion with - by activating it just before the ultimate hits
 * Any champion with - as long as the shield is up
 * ,, , , and  - They all have abilities who allow them to become untargetable right before Requiem hits them. It should be noted that  and  require a nearby enemy target,  require a nearby enemy champion, though.
 * Any champion with - if the passive is up - although note that the passive will be lost and it has a longer cooldown than Requiem.
 * ,, and - They all have passives which allow them to revive after taking lethal damage. As long as their passive is ready for use, they cannot be killed by Requiem.
 * and - Both have spellshields.
 * - by casting (she can also cast it on allies, making them immune to Requiem too)
 * - by activating
 * and - Both have ultimates which, if timed properly (right before Requiem hits) will leave them immune to the Requiem damage.
 * - If there is a nearby enemy champion, she can activate to become completely immune to Requiem's damage (Cannot target ).
 * Any champion who has been made an by  - If she has her ultimate up, she can activate it to protect her Oathsworn from being killed by Requiem
 * Any champion who has been affected by
 * - If there is a on any place of the map, Rek'Sai can use  to teleport to them. During the teleport she is considered to be untargetable, so a well-timed Void Rush can dodge Requiem.
 * - If she invests on AP, she can use on herself or any ally to make them not die to Requiem.
 * - behaves like a spellshield, making Fiora immune to Requiem's damage if timed properly.
 * - If is up, she can cast it on herself to become completely immune to Requiem.
 * - By casting on himself and/or an ally, he can make them completely immune to Requiem.
 * Any allied champion who has been devoured by
 * - If well-timed, can make him untargetable and allow him to avoid Requiem. It is suggested to activate Grand Skyfall at the second that Karthus starts channeling.
 * - With they can protect themselves and anyone inside the area from dying.

Champion Spotlight
Karthus is a powerful and persistent solo lane mage. Whittle your enemies down with repeated casts of Lay Waste, using smart positioning and timing to deal extra damage to lone targets. When your jungler comes in to gank, throw down Wall of Pain and activate Defile to deal huge area of effect damage to your slowed enemies. Even if they get away, they’re still not safe from Requiem, a colossal global ultimate that devastates every enemy champion on the map.