League of Legends Karthus players will likely find him to be a dynamic champ to build out properly. You'll find that his build is modified when he is fighting either well-rounded or homogenous team compositions, meaning you shouldn't select the same Karthus build every single round of League of Legends
The most critical items to incorporate into your champ's build are: Affliction de Liandry, Coiffe de Rabadon, and Bâton du vide. Players who added these items in their builds had a greater winrate than players who tried for other Karthus builds. Likewise, if you are battling a mixed enemy team comp, you should strongly consider getting Karthus the Inspiration, and Domination runes. In recent games, he won the largest number of his matches when built with these runes.
We came up with our Karthus build guidance by examining 33 687 recently ranked LoL games with him selected. We only recommend the highest winrate Karthus builds that were used by ranked players enough times for us to advise them. With so many games in our data, we are quite confident in our suggested builds.