Clever use of enemy ultimates can open up new possibilities to approach teamfights.
Wait for you or your enemy to reach low health before using Kingslayer for maximum effect.
Space out your ability usage to get maximum effect from Petricite Burst.
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 Sylas 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, Sylas sees a large worsening in his KDA (ratio of kills and assists to deaths) when paired with Karthus. His KDA worsened from NaN to NaN. This decrease shows that Karthus helps Sylas perform poorer in ranked League of Legends games. Yet, the small difference indicates that this performance change is not very impactful.
When Sylas is an ally to Karthus, he gets a little decrease in his full damage dealt. This change could indicate that Karthus does not help cover for him to deal more damage or that his presence on the team also helps extend the game's duration. Similarly, when Sylas is played with Karthus on the same side, he usually scores many fewer killing sprees compared to when he plays alone. This is contrasting evidence that he is worse when playing alongside Karthus.
Moreover, when Sylas plays with Karthus on the same side, he often receives a little more damage than when he fights alone. Receiving more damage may indicate that Karthus does a poor job of protecting Sylas during teamfights.
There is no universally accepted best synergy for Sylas that will always be his #1 teammate. However, Karthus is a terrible ally for Sylas. By being on the same team as Sylas, he drops their win rate by -4.5% to 44.5%. This demonstrates that there is a terrible synergy between Sylas and Karthus that allows them to perform worse together than without each other.
Karthus has a greater difficulty than Sylas. That means Sylas players must be careful when finding Karthus comrades to play with, as they will need a greater level of skill to do well with you.
Fighting on the same side, Sylas players should see an overall large increase in your team’s capability to deal magic damage. Combined, these champions can deal quite a lot of AP type damage.
Although, by aligning Sylas and Karthus together, you will not be granting your other allies a great deal of AD. Plan to have other champs on your team that fills this relative hole in this pairing's potential.
Regardless of the skill of your Karthus teammate, you should focus on increasing your income, warding to avoid ambushes, and taking down objectives. If you do this, you will do well anyway.
If you would like to truly master Sylas in order to work well with Karthus during both the lane and mid / late game phases of League, you should continue reading to master some more tips and tricks for this champion pairing. If you pay attention to the build and stats displayed above, you will grow your win rate by a lot.
The ideal finished items to include in your Sylas and Karthus synergy build include Rabadon's Deathcap, Shadowflame, and Stormsurge. When Sylas bought at least these three great items in his build, he did significantly better when fighting alongside Karthus than with most other commonly used builds. In fact, Sylas boasted an average winrate of 44.5% when synergizing his build and playstyle to Karthus with these items in his kit.
To have the highest likelihood of defeating your oponents, Sylas players should use the Electrocute, Sudden Impact, Eyeball Collection, Relentless Hunter, Scorch, and Transcendence runes from the Domination and Sorcery rune sets. Out of all the rune sets players picked for this team composition, this combo of runes resulted in the best win rate. Moreover, these runes gave a 44.5% win rate overall.
By default, tips, statistics, and builds on how to synergize Karthus with Sylas are presented for all skill levels, merged. To narrow the statistics and builds to a specific player tier, you may use the selection menu at the top of this page.