Let's get to the point, Karthus is all about the Requiem. This build, is all about the requiem.

In all seriousness though, this build is very squishy and should only be piloted if you know how to stay alive and aren't the type to recklessly charge and take risks constantly. It's a lot of fun to play though, with ridiculously high AP and sufficient magic penetration throughout mid and late game.

Pros:
-stupid damage (especially late game)
-Requiem

Cons:
-ultra squishy
-needs good Q farming
-weak at ganking early (we want to farmmmmmm)

With this build, note that you will be dying in team fights early, during those you want to maximize damage output by using Q as much as possible with your high AP and magic pen, and then using Revive+Requiem to finish off if necessary (Revive has long cool down so be judicious in use). That's not to say that it's not okay to Requiem during death, but this build is most useful when you spam Q effectively.

Magic Penetration.


'nuff said

We want to max our magic penetration and AP, the mana is for additional AP via endgame Archangel staffs, it's also useful for early game farming when we can be mana hungry.

We build tear first, which we will proc to 1000 mana as quickly as possible, by only using Q to farm. Do NOT use Defile to farm early game - it's just simply too mana hungry and will not proc your tear to 1000, once the tear/archangel staff is near 1000 mana, then using defile is okay.

Magic Penetration Boots - Necessary for getting past pesky MR. Note that most heroes have a base MR of 30. With MP runes and masteries and these boots we will have about 35-40 magic penetration which is more than enough for the squishy heroes. Tanks with high MR will be a problem, but then again, the game is all about killing those squishy carries.

Rabadon Deathcap+ 4 Archangel Staffs=1200AP, with plenty of mana to defile and lay waste to your heart's content. Need I say more?


With Karthus Lay Waste and Defile, we should be able to farm up the whole build within a reasonable amount of time.

We level Lay Waste first to farm, with Defile to supplement our mana regen as we last hit. Up to about level 10, we will exclusively farm with somewhat low emphasis on ganking, hence we leave the wall to much later.

Revive - Use very sparingly and intelligently, but do not be afraid to use. During death, we want to use Q rather than requiem, if we have revive up, as this will result in far greater damage output.

Teleport - overall useful spell, lets us get where we want to farm, and combined with Revive can make for some upsetting plays to the other team with karthus massive aoe damage.

This build is very squishy, hence should only be used by players who are advanced enough to know how to stay a safe distance away while harassing with Lay Waste. We should always proc our tear and use Lay Waste to scout.

Early game:
Farm, stay alive

Mid game:
Farm, Requiem's

Late game:
Farmed up already, stay alive, Requiem's