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.
Gwen can still damage enemies outside her Hallowed Mists, especially with her Ultimate's range.
Some of Gwen's Abilities can apply her passive to multiple enemies, so aim them at groups to get maximum damage and healing.
Always be Attacking - In addition to dealing bonus damage, Gwen's Attacks empower or reset many of her Abilities.
The Karthus Gwen synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Gwen, 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 Gwen. His KDA worsened from NaN to NaN. This decrease shows that Gwen helps Karthus perform worse in ranked LoL matches. Yet, the small difference demonstrates that this performance change is not very impactful.
When Karthus plays on the same team as Gwen, he sees a little drop in his full damage output. This change may indicate that Gwen does not help cover for him to dish out more damage or that her allyship also helps extend the game's duration. Similarly, when Karthus is played alongside Gwen on the same team, he usually scores many fewer killing sprees than when he plays without Gwen. This is contrasting evidence that he is worse when playing alongside Gwen.
Moreover, when Karthus plays with Gwen on the same side, he on average receives a little less damage than when he fights alone. Taking not as much damage could indicate that Gwen does a decent job of covering Karthus in teamfights.
There is no ideal ally for Karthus that will 100% of the time be his best ally. Yet, overall, Gwen is a very bad ally for Karthus. By being on the same side as Karthus, she decreases their win rate by -3.1% to 44.2%. This proves that there is a terrible bond between Karthus and Gwen that results in them performing not as well together than alone.
Gwen has a lower difficulty than Karthus. That means you don't need to be careful when finding Gwen comrades to go into battle on the same side as, as they will have to have a lower level of skill to play well with you.
Working together, you should expect to see an overall large increase in your team’s capacity to deal magical damage. Combined, these champs are able to dish out a surprising amount of magic type damage.
Conversely, by bringing Karthus and Gwen together, you may not be giving your other allies enough tankyness. We recommend you include other champions on your team that nullifies this relative gap in their capabilities.
Regardless of the ability of your Gwen ally, you need to focus on maximizing your income, outlasting your enemies, and taking down objectives. If you heed this simple advice, you should do well, regardless.
If you would like to truly master Karthus to synergize with Gwen during both the early game and mid / late game phases of League of Legends rounds, you should continue reading to master additional tricks and insights into this champion pairing. If you mind the build and suggestions shown above, you will increase your win rate by a lot.
The top items to have in your Karthus and Gwen synergy build include Rabadon's Deathcap, Malignance, and Liandry's Torment. When Karthus included at least these three finished items in his build, he did a lot better when fighting alongside Gwen than with most other common item sets. In fact, Karthus had an average win rate of 44.2% helping carry Gwen with these items in his kit.
To have the greatest likelihood of beating your oponents, you should equip the First Strike, Magical Footwear, Future's Market, Cosmic Insight, Eyeball Collection, and Ultimate Hunter runes from the Inspiration and Domination rune sets. Of all the rune combinations players used for this champion pairing, this blending of runes yielded the best win rate. Notably, these runes gave a 44.2% winrate overall.
If you would like to get Karthus with Gwen collaboration tips and stats for a a distinct division rank, feel free to choose one from the selection menu above. If viewing for the first time, the stats and guides given are computed using all rounds run with these champs.