karthus is one of the greatest champions the game he's strenght is that he has extremly low cooldowns he isnt hard to play but hard to master so he can kill in late game this guid will tell you my way to own early and late game.

i would appreciate if you dont vote before trying it and leave a comment if voting down and tell whats wrong so i can try it out and see if i think the same and chance the build

try also to check out the build that there helped me when i stareted as karthus its a great guide he has with a lot of nice detailes http://www.mobafire.com/league-of-legends/build/karthus-cthulhus-right-hand-52115

Pros

great farmer
extrem low cd
epic ulti
epic passiv
great h***aring
get easy feeded
great AoE dammage with all dammage spell
best speed lower in game

Cons

hard to keep good in late game(not impposibil)
need to be mid
slow

greater mark of insight is a the best to all mage after as spell penetration is the best mark for mages


greater seal of clarity is great to get a little MR even because even with defile off its nice with some MR you can ofc swith togreater seal of replenishmentgreater seal of replenishment


greater glyph of potency is great with all mage but if you wan you can ofc swith it out with greater glyph of force


greater quintessence of potency is also great with all mages so ofc i use it here you can still swith to greater quintessence of force

death deified is there not to much to about exept that it is the reason for why you dont have to be afraid of die because yo would normal get a kill when you die

Lay waste is your main spell in the start try to use it to get your enemy when he is hiding beside the turret but be carefull you will not go too close and get hit by the turret. when the minions game use this spel for farming and h***aring your enemy when going after your enemy try to only hit them so you dammage 2 time more


wall of pain is karthus main ganking tool use this to stop enemy from fleeing or to help you and your team with escaping this is also great when you die so your enemys has harder to get to safty from you atlast it can be used in early game to make it easyer to hit with Lay waste


defile is a the second spell you wan to upgrade half becausee that when its of its make sure you dont run so easy out of mana and half because it would could get up and do great AoE dammage and will could take out any minion push on unter ten sec however in early game i experince that it gives just that dammage you mostly need when you are fighting and enemy so rember to turn it on if you go in to a direkt fight. its also great to scarry your ennemies away.


requim is one of the best ulti in the game because its dammage all so make sure your team say when they need you to cast it and els just use it wies i normal also use it when i die that gives me some kills normal but if you fell that it isnt a good idea then just dont do it.

sapphire crystal i think is a great start item because the 200more mana combine with the 2x healt potions should be abel to give you alot of time with farming and h***aring before you need to rec plus if it goes in a direct fight you will definly need the mana to keep defile on


sorcere's shoes is a most for the almost all mage because of its MP and speed but ofc if you feel he is too slow you can try with i have concider it but never tryed so if you do it would be nice if you leave a comment because if its better i migt wanna add it in the build insted of sorcerer's shoes


rod of ages is what i would call the next step because with the more health you shoul could surive longer but i get the understand that some might wanna getarchangels staffarchangels staff insted however i fell thhat the hp is better spend than the MR because of defile will in the most games be enoght to keep your mana on 100% until you get in a team fight and turn it on but with all the mana you got your chance for lose all your mana is smallso i fell the cold is better spend in rod of ages


is just what you need now to get your AP up and also this is most for all mages


rylais crystal scepterrylais crystal scepter is also great not just because of all the hp and ap but also because of its passive that for karthus only gives 15% slow down but its still enought to hold them close when first your has hit them so this hould make sure that even when your wall of pain is on cd they cant escape you but if you dont have this item before the team fights start you might wanna drop it and go for one more hextech gunblade insted after some the passiv dont help that much in team fights and the 25% more spell whamp should do nicly and make it even harder to kill you


will of the ancients is great after as it does not just give you ap and spell whamp but gives it to all alaise close to you that should give your team a great + in team fights and will alow you to get health from minions before going in a team fight however remember to check if anyels from your team have buyd one because if there is that its just a waist of cold then you would rather spend your money on one more hextech gunblade insted


hextech gunblade i have selected because of the spell whamp and its ok ap but most because of the spell whamp after as this + will of the ancients gives you a great surivel abbility but in the most team figths where no teams is over feeded you will still die because you would get target quick but the time you get from this two items + your passiv death defied should could chance the fight so your team win if you as you normal will be is feeded you will when you get this item be abel to go in a fight alone with the other team and get two kills however i recomand you dont do this if not you have to because it can make some people on your team mad and report you (but its funny after when you go down to the other theam alone they just run xD)

flash is a must to karthus its great for porting close to you enemy so your defile can hit combine this wall of pain and spawn Lay waste. as always it can be used as a way to escape.


this is great to get quick around and thats a good thing with karthus however this i wouldnt call a must so if you dont fell for it just take another

Karthus is one of the greates farmer in the game hes main farming tool is lay waste with this you should go after the rangded minions first because they have the lowest life and when you got defile in 5 you would be abel to kill minions and get mana from it also if you need to kill them quick just turn it on and walk by and they would normal be dead but then you dont got any mana from it

in team fight karthus is very strong you would normal qouck get target so turn on defile before you go in so your spell wamp works immediately then spawn Lay waste when they start running use wall of pain and when you die or the fight is almost over use requim to get them who run or almost is dead