Karthus, the Deathsinger is a ranged mage champion whose abilities specialize in dealing heavy sustained damage in an area of effect fashion. Capable of dealing damage from both near and afar, Karthus excels at both inflicting constant harm to the enemy team from a distance as well as decimating the enemy team's collective health pool through the application of a high-risk, high-reward, self-destructive playstyle.

Pros:
-good laning face
-nice defence
-GLOBAL ULT
-nice damage

Cons:
-no escape spells
-can be mana hungry
-quite hard to master

Flash

I chose this spell because karthus requires an escape tool, and Flash is the best choice for that.

Exhaust


I chose this over Ignite because with Exhaust, you can land more Lay Waste on your enemy, thats more damage than what ignite gives. It can also be used defensively to get away and lessen the damage taken.

Death Defied

Upon dying, Karthus enters a spirit form and becomes invulnerable and untargetable, allowing him to continue casting spells at no cost for 7 seconds. This gives you a second chance to kill someone, pretty sweet passive for a spammer like karthus.


Lay Waste
RANGE: 875 COST: 20 / 26 / 32 / 38 / 44 MANA COOLDOWN: 1

ACTIVE: Karthus creates a point of unstable magic at the target location that detonates after a 0.5 second delay, dealing magic damage to enemies in a 200*-radius area. Lay Waste deals double damage against isolated targets. This is one of my favourite spells, it deals DOUBLE damage to single units and it has a 1 second cooldown :).


Wall of Pain
RANGE: 1000 COST: 100 MANA COOLDOWN: 18

ACTIVE: Karthus creates a wall of energy between 2 obelisks at target position for 5 seconds. Enemies who pass this wall have their movement speed Slow icon reduced by a large amount and their magic resistance reduced by 15% for 5 seconds. Movement speed gradually recovers over the duration. I use this spell to land more Lay Wastes on an enemy, since it has a nice slow. You can also use this to keep an enemy in your Lay Waste range when your passive activates.

Defile
RANGE: 425 COST: 30 / 42 / 54 / 66 / 78 MANA PER SECOND

TOGGLE OFF: When Karthus kills a unit, he restores mana.

TOGGLE ON: Karthus surrounds himself with the souls of his victims, draining his mana to deal magic damage to enemies in range each second.

This skill can be used for restoring mana, especially for karthus, since he losas a lot of mana from spamming Lay Waste.


Requiem
RANGE: Global COST: 150 / 175 / 200 MANA COOLDOWN: 200 / 180 / 160

ACTIVE: After channeling for 3 seconds, Karthus blasts all enemy champions on the map and deals magic damage. This is Karthus' signature move, i like to use this spell when my passive activates so it cannot be cancelled by CC.

Standard combo:

Defile > Wall of Pain > Spam Lay Waste

Surprise:

Flash > Defile > Exhaust > Wall of Pain > Spam Lay Waste

All Out:

Defile > Wall of Pain > Spam Lay Waste > Requiem

Soecial Combo:

Run to enemy team > Defile > Spam Lay Waste > Die > Wall of Pain > Spam Lay Waste > Requiem

Here are a few tips to help you with Karthus:

-Use

Lay Waste to farm faster and deal more damage

-Dont be afraid to spam your skills once you get Tear of the Goddess

-Try to use Requiem in a safe area where you wont die or get CC'd

-Make the most of your passive since you do not use mana

-Start a fight by turning on your Defile

-Try not to panic upon dying since you have Death Defied

Hi guys im NuclearBurrito, I just started plaing LoL a few months ago, right now I am silver 3.
I mainly play AP as Heimerdinger, Karthus, and Xerath. This is my first guide so please.... have mercy ;). Anyway, see you guys on my next guide!