Try and keep targets in the range of your Flamespitter. It can deal a lot of damage overtime.
If you are winning a fight you can use your ultimate to wall off an escape path.
Try and pace yourself to stay in the Danger Zone to maximize your effectiveness. It is easy to overheat if you rapidly use your abilities.
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.
The Rumble Karthus synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Karthus, compared to his overall stats. Significant differences are areas of focus that highlight how his gameplay changes when paired with this other champion.
Overall, Rumble sees a large worsening in his KDA (ratio of kills and assists to deaths) when paired with Karthus. His KDA went down from NaN to NaN. This decrease shows that Karthus helps Rumble perform poorer in ranked League of Legends matches. Yet, the small difference demonstrates that this performance change is not very impactful.
When Rumble is paired with Karthus, he observes a little decrease in his full damage output. This difference may indicate that Karthus does not help cover for him to deal more damage or that his presence also helps extend the match's duration. Similarly, when Rumble is played alongside Karthus 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 alongside Karthus.
Moreover, when Rumble plays with Karthus on the same side, he usually receives a little more damage than when he plays alone. Taking more damage could indicate that Karthus does a poor job of protecting Rumble in team fights.
There is no top champion pairing for Rumble that will 100% of the time be his top ally. Yet, overall, Karthus is a terrible ally for Rumble. By locking into the same side as Rumble, he decreases their win rate by -6.8% to 42.5%. This shows that there is an easy to overcome and exploit bond between Rumble and Karthus that results in them performing not as well together than alone.
Karthus has a much lower diffuclty than Rumble. That means you don't need to be cautious when arranging Karthus comrades to go into battle on the same side as, as they will require a much lower level of skill to be able to fight well with you.
When playing on the same side, you should expect to observe an overall large increase in your team’s capability to deal magic damage. Together, these champs can deal quite a lot of AP type damage.
Although, by aligning Rumble and Karthus together, you probably will not be granting your other teammates enough sustained damage output. Make sure to have other champions on your team that nullifies this relative gap in their potential.
Regardless of the ability of your Karthus teammate, you should focus on maximizing your income, staying alive by avoiding foolish fights, and taking down objectives. If you do this, you will do well anyway.
If you would like to truly master Rumble to work well with Karthus during both the early game and mid / late game phases of League of Legends rounds, you should keep reading to pick up some more lessons on this champion pairing. If you mind the build and stats shown above, you will grow your win rate by a lot.
The ideal items to focus on in your Rumble and Karthus synergy build include Zhonya's Hourglass, Stormsurge, and Liandry's Torment. When Rumble used at least these three finished items in his build, he did a lot better when paired up with Karthus than with many other typical item sets. In fact, Rumble boasted an average winrate of 42.5% when playing alongside Karthus with these items in his kit.
To have the greatest chance of vanquishing your oponents, you should use the Arcane Comet, Nimbus Cloak, Absolute Focus, Scorch, Bone Plating, and Unflinching runes from the Sorcery and Resolve rune sets. Of all the rune sets players picked for Rumble and Karthus pairings, this blending of runes yielded the best win rate. In fact, these runes averaged a 42.5% win rate overall.
By default, tips, stats, and builds on how to pair Karthus with Rumble are presented for all skill levels combined. To narrow the statistics and builds to an individual skill level, you should use the selection menu earlier in the counter matchup guide.