I think a lot of us know how to play Karthus well at this point, and there are some good tools to discover how to do so, watching streams or tourny matches and the like, all are great methods.
However I thought it would be equally valuable to tell you how NOT to play Karthus, so that you don't get confused or mess up your build mid game because you're cooking your Cheetos in the microwave with some Dulce de Leche con Flan.
Here we will not be going over anything you should do in a game. I'm not a Karthus pro and I'll leave the proper methods and their explanations to the professionals. Here, we will be going over my own personal expertise... Which happens to be what you should NEVER do when playing Karthus.
Wow, those items.
Marvelous isn't it?
Doran's blade, because I can't play AP champions to save my life, and therefore I am bad at League of Legends.
HoG; more gold, are you bad? Ofc we want more gold. Also, I've got a hot date with Morganna and if she sees my heart of Gold maybe she'll like me more! 8D
Berzerkers greaves, and again, this is because I am bad at League of Legends and the sum of my educational career amounted in me being able to tie my shoes correctly on 55% of my attempts.
Oracles on a champion who's passive allows him to not fear death as much as the average champion. Nope, we WANT to fear death, we are going to CREATE that fear where fear need not exist. Oracles all day every day!
Soraka is a counter to Karthus? HAH... Says who? Just wait till I come to lane with my Executioner's Calling you fool, then we'll see who counters who... Oh, and good luck healing... *****.
Obviously the next item in line is Atma's Impaler. This is the logical choice to pair with my Executioner's Calling. That's called SYNERGY folks. Synergy. Get learned.
What's left to buy? It already looks so perfect. Nashor's Tooth, the SLAM DUNKEROO. The time has come to strike fear and confusion into your enemies hearts, and believe me, at least one of those things is going to happen when you show up to your next teamfight.
Cherry on top? Frozen Mallet. You mad, bro?
Duff, those masteries look good though.
No. No they don't.
Slap yourself, dump a bucket of ice water on your head, do whatever you need to do, but please realize that those masteries are complete garbage.
Are we going to be pushing any towers with Karthus?
Well, on second thought, yes you very probably will be, if you're dumb enough to take masteries like these ones, so never you mind.
Runes, Duff, explain please?
What is this. I'm scared.
Is... Is that a ****ing... Are those 4 seals of Might?
So good, right?
I don't take my ultimate until last because global map presence is over rated and boring.
I'd rather just aggressively kick my enemy's *** you know? And KS'ing with ult is stupid and if your team can't get the kill on their own then they are baddies. If I never ulti then my opponent can't use the excuse that I got fed on other lanes, they have to recognize that I am more skilled than them and deal with it.
So I just max Defile. Oh and I suck at skillshots and I can't aim and sometimes I get confused which team I'm on and end up targeting my own team mates, so I don't get Lay Waste untill I have to, but it is still a little better than my ult so I get it before that.
I like to max defile and the wall skill because the Synergy is too good with my items.
And then from there, I bombarb my enemy with auto attacks, which usually makes me forget to use my Q which is another reason why I don't level it at all early. Why Q, when I can crit..?
You know, it's really all about good synergy, at the end of the day, and this is what works best for me!
Also when you land a wall, they can't escape, so you can Promote a minion and watch the destruction happen. I have gotten killed a lot doing this but sometimes it works really well. Also if you use Surge at a good clutch moment you can really win the fight for your team it's really amazing when you think about my items and the skills I use you should certainly never try this.
Playstyle with Karthus.
Well since you have an Oracle, you really won't want to be dying very often.
You're going to want to kite along the outside.
If you're lucky, you can hit something, maybe some minions with your Defile.
They tell me Lay Waste is better but obviously not because I can't ever land it so uhm the jokes on them stupid people.
I mean I'm pretty sure it was supposed to be a targeted skill but they forgot to add the target into League because it seems like it's broken and just follows my cursor like it loves my cursor or something lol, you know what I mean? Like wow Riot way to make your skills love my cursor lol, I bet you feel stupid now Riot hahahahah idiot.
So you'll wanna kite around the edges of fight and it's better if you just use your ult every time it's on cooldown because it really sucks in team fights and to be honest it does like zero damage and feels useless which is why I barely max it like ANY DAY Riot you'll buff Karthus ****ing ult so maybe I'll finally win a game. Make it scale off of AD too please so my build works with his kit better you morons.
So yeah just spam ult whenever it's off CD, at least it'll count towards like one auto attack in lane or whatever and their Sona will probably just heal it off in like two skills or whatever but it's better than nothing. Fking useless ult...
So because you have Oracles you don't wanna die, so you need to play carefully and this is going to require skill, and it's skill you may not have but if you can pull it off just right it's amazing man I have won at least 4 games over the past 3 weeks using this strategy and I play Karthus like 4 games a day because I want the best technique and this works for me really well.
I mean when you really think about it Karthus passive sucks because dying is for noobs and you're gonna have a horrible KDA at the end of the game so **** his useless passive, pros never die ever and im getting better i usually go negative in most games but im getting better and the other day i even went 7/5 so im getting good ok?
Yeah so that's sorta the core concept. Use auto attacks on squishy targets, it hurts a lot more that way but don't get focused down because you can't auto attack with your ****ing worthless passive only cast spells.
Hopefully by now you have a pretty good and clear idea of how you should NEVER under ANY circumstances play Karthus.
Good luck not doing any of this ****, summoners!