League of Legends Karthus players may find him to be a complex champ to build out properly. You will see that his build varies when he is playing against either well-rounded or highly focused team compositions, demonstrating you shouldn't select the same Karthus build every round of League of Legends
The most important items to incorporate into your champ's build are: Liandrys Leid, Rabadons Todeshaube, and Leerenstab. Those who added these items in their gear had a greater win rate than those who used other Karthus builds. Likewise, if you are trying to beat a varied enemy team comp, you should really consider grabbing yourself the Inspiration, and Dominanz runes. In recent games, he won the greatest number of his matches when built with these runes.
We set our Karthus build recommendations by examining 19.947 recently ranked League of Legends matches with him in them. We only recommend the highest winrate Karthus builds that have been used by ranked players enough times for us to advise them. With so many rounds in our dataset, we are quite confident in our suggested builds.