Lay Waste is very strong at farming minions and harassing enemy champions.
Ask your allies to help point out when you should use Requiem to get kills in different lanes.
Kassadin's ultimate has many uses and is on a shorter cooldown than most, use it often.
Kassadin has multiple item paths; he can go caster via Mana and Ability Power or anti-caster with Cooldown Reduction and Magic Resist.
Try to get the Ancient Golem buff to counteract Riftwalk's increasing Mana cost.
The Karthus Kassadin synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Kassadin, compared to his overall stats. Significant differences are areas of focus that highlight how his gameplay changes when paired with this other champion.
Overall, Karthus sees a very large drop in his KDA (ratio of kills and assists to deaths) when paired with Kassadin. His KDA went down from NaN to NaN. This drop shows that Kassadin helps Karthus perform poorer in competitive League games. Yet, the small difference shows that this performance change is only marginal.
When Karthus is an ally to Kassadin, he observes a little decrease in his complete damage dealt. This may indicate that Kassadin does not help cover for him to dish out more damage or that his allyship also helps increase the match's duration. Similarly, when Karthus is played together with Kassadin on the same team, he usually scores many fewer killing sprees than when he plays on his own. This is contrasting evidence that he is worse when playing with Kassadin.
Moreover, when Karthus plays with Kassadin on the same side, he usually receives a little more damage than when he fights alone. Getting dealt more damage may mean that Kassadin does a poor job of covering Karthus during team fights.
There is no perfect synergy for Karthus that will always be his top synergy. However, overall, Kassadin is a very typical ally for Karthus. By locking into the same side as Karthus, he raises their win rate by 0.2% to 47.5%. This shows that there is only a small bond between Karthus and Kassadin that results in them performing better together than alone.
Kassadin has a greater difficulty than Karthus. That means Karthus players must be careful when arranging Kassadin allies to play with, as they will have to have a greater level of skill to be able to play well with you.
Playing together, Karthus players will likely see an overall large increase in your team’s capacity to deal magical damage. When paired, these champions are able to dish out a surprising amount of magic type damage.
Although, by aligning Karthus and Kassadin together, you may not be giving your side enough AD. We recommend you bring other champions on your team that nullifies this gap in this pairing's capabilities.
Regardless of the skill of your Kassadin ally, you should focus on increasing your gold income, staying alive by avoiding foolish fights, and clearing objectives. If you heed this simple advice, you should do well, regardless.
To truly master Karthus to synergize with Kassadin during both the early game and mid / late game phases of League of Legends rounds, you should continue reading to learn a few extra lessons on this champion pairing. If you use the build and tips shown here, you will increase your win rate significantly.
The most important finished items to have in your Karthus and Kassadin synergy build include Rabadon's Deathcap, Malignance, and Liandry's Torment. When Karthus used at least these three great items in his build, he did significantly better as an ally of Kassadin than with many other commonly used item sets. In fact, Karthus had an average winrate of 47.5% when synergizing his build and playstyle to Kassadin with these items in his kit.
To have the best chance of defeating your oponents, Karthus players should take the First Strike, Magical Footwear, Future's Market, Cosmic Insight, Eyeball Collection, and Ultimate Hunter runes from the Inspiration and Domination rune sets. Out of all the runes we have analyed for this champion pairing, this set of runes resulted in the greatest win rate. Notably, these runes averaged a 47.5% win rate overall.
By default, tips, stats, and builds on how to synergize Kassadin with Karthus are presented for all ranked divisions. If you want to narrow the statistics and builds to a particular player tier, you can use the selection menu above.