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.
Use Demacian Standard as a scouting tool when worried about incoming enemies.
You can use the Dragon Strike / Demacian Standard combo to get out of your own Cataclysm arenas.
Split your basic attacks on different champions at the beginning of fights to maximize damage.
The Karthus Jarvan IV synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Jarvan IV, 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 large worsening in his KDA (ratio of kills and assists to deaths) when paired with Jarvan IV. His KDA fell from NaN to NaN. This decrease shows that Jarvan IV helps Karthus perform worse in ranked League of Legends games. Yet, the small difference shows that this performance change is only marginal.
When Karthus is an ally to Jarvan IV, he gets a little increase in his total damage dealt. This could signal that Jarvan IV provides protection for him to dish out more damage or that his support also helps extend the round's duration. Similarly, when Karthus is played alongside Jarvan IV on the same team, he usually scores many fewer killing sprees compared to when he plays without Jarvan IV. This is contrasting evidence that he is worse when playing alongside Jarvan IV.
Moreover, when Karthus plays with Jarvan IV on the same team, he usually receives much less damage than when he fights alone. Getting dealt not as much damage may mean that Jarvan IV does a decent job of protecting Karthus in teamfights.
There is no top synergy for Karthus that will no matter what be his #1 ally. However, Jarvan IV is a relatively poor teammate for Karthus. By being on the same team as Karthus, he lowers their win rate by -1.3% to 46.0%. This signals that there is a bad bond between Karthus and Jarvan IV that results in them performing not as well together than without each other.
Jarvan IV has a lower difficulty than Karthus. That means Karthus players don't need to be careful when lining up Jarvan IV teammates to go into battle on the same side as, as they will require a relatively low level of skill to be able to do well with you.
Playing on the same side, Karthus players should observe an overall large increase in your team’s ability to deal magical damage. Together, these champions are able to dish out a surprising amount of magic type damage.
Conversely, by pairing Karthus and Jarvan IV together, you probably will not be giving your other teammates a great deal of attack damage. We recommend you have other champs on your team that nullifies this gap in their capabilities.
Regardless of your Jarvan IV ally's ability, you need to focus on increasing your income, warding to avoid ambushes, and taking down objectives. If you do this, you should do well anyway.
To truly master Karthus in order to work well with Jarvan IV during both the early game and mid / late game phases of League, you should keep reading to learn some more tips and tricks for this champion pairing. If you mind the build and suggestions displayed here, you will grow your win rate significantly.
The best finished items to prioritize in your Karthus and Jarvan IV synergy build include Malignance, Void Staff, and Liandry's Torment. When Karthus used at least these three items in his build, he performed much better when fighting alongside Jarvan IV than with many other typical builds. In fact, Karthus boasted an average win rate of 46.0% helping carry Jarvan IV with this build.
To have the highest chance of defeating your oponents, you should equip the Dark Harvest, Cheap Shot, Eyeball Collection, Ultimate Hunter, Presence of Mind, and Last Stand runes from the Domination and Precision rune sets. Out of all the runes players chose for this champion pairing, this mix of runes yielded the top win rate. Moreover, these runes provided a 46.0% win rate overall.
If you need to view Karthus and Jarvan IV cooperations tips and stats for a a particular rank, please choose one from the selection menu shown above. By default, the stats and guides displayed are computed using every game finished with these champs.