Talk:Karthus/@comment-77.105.20.210-20120526163118/@comment-76.229.139.77-20120527180344

cdr is questionable on karthus. q and e dont really benefit, with max cdr w will have 10.8 sec cd, and will still probably only be used once in teamfights (unless enemy stays near karthus spirit after he dies) so only r benefits a lot from cdr. not saying cdr is unviable, but questionable. so i would only get dfg if you need the active.

getting RoA and rylai is also questionable. not saying one is better over the other, which has been debated on this page for eons, but getting BOTH might not always be a good idea. if you need the extra health from both, thats okay. if you get RoA for mana, get Tear instead.

Tear (to archangels) is the biggest problem with your build. u said it would require a lot of spamming to charge? karthus is made to spam. also, archangels pays for itself even if it only provided mana regen. archangels build cost is 1000 and provides 25 mana regen. the Tear in the build of archangels provides 7 mana regen, so if archangels ONLY gave mana regen, its 18 mp5 for 1000g. using meki pendant unit rate is about 18 mana regen for 1003g. Adding the huge ap and mana archangels gives, archangels is more than worth what you paid.

skill order: leveling q is crucial, but if against melee champs leveling defile can give a higher damage output. dont level wall last, level it when the teamfights start. which usually means you'll level it last anyway.

runes are fine. seals are meant for defense though, they save ip if you invest in defensive seals like health/lvl. masteries i usually take 21/0/9, but i suppose 9/0/21 is fine too, with so many offensive runes.

everything else seems fine