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.
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.
The Kassadin Sylas synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Sylas, compared to his overall stats. Significant differences are areas of focus that highlight how his gameplay changes when paired with this other champion.
Overall, Kassadin sees a very large drop in his KDA (ratio of kills and assists to deaths) when paired with Sylas. His KDA decreased from NaN to NaN. This negative change shows that Sylas helps Kassadin perform worse in ranked League of Legends games. Yet, the small difference shows that this performance change is not very impactful.
When Kassadin is paired with Sylas, he sees a little drop in his full damage output. This difference may indicate that Sylas does not provide protection for him to deal more damage or that his presence on the team also helps extend the match's duration. Similarly, when Kassadin is played together with Sylas on the same side, he usually scores many fewer killing sprees than when he plays alone. This is contrasting evidence that he is worse when playing with Sylas.
Moreover, when Kassadin plays with Sylas on the same team, he on average takes a little less damage than when he fights alone. Getting dealt not as much damage could indicate that Sylas does a decent job of covering Kassadin during team fights.
There is no one best champion pairing for Kassadin that will 100% of the time be his ideal synergy. However, overall, Sylas is a not very good companion for Kassadin. By being on the same team as Kassadin, he decreases their win rate by -1.2% to 48.8%. This proves that there is a harmful bond between Kassadin and Sylas that allows them to perform worse together than without each other.
Sylas has a much lower diffuclty than Kassadin. That means Kassadin players don't need to be very careful when lining up Sylas teammates to play with, as they will have to have a much lower level of skill to be able to play well with you.
Playing cooperatively, you will likely witness an overall large increase in your team’s capacity to deal magic damage. Combined, these champs can deal quite a lot of AP type damage.
Although, by bringing Kassadin and Sylas together, you probably will not be giving your team a great deal of sustained damage output. Plan to pick other champs on your team that neutralizes this relative gap in this pairing's playstyle.
Regardless of your Sylas ally's skill level, you should focus on maximizing your gold income, warding to avoid ambushes, and taking down objectives. If you do this, you will do well anyway.
To truly master Kassadin to synergize with Sylas during both the laning and mid / late game phases of League of Legends matches, you should continue reading to pick up a few extra tips and tricks for this champion pairing. If you use the build and stats presented here, you will grow your win rate by a lot.
The most important finished items to build first in your Kassadin and Sylas synergy build include Seraph's Embrace, Zhonya's Hourglass, and Rod of Ages. When Kassadin incorporated at least these three finished items in his build, he performed much better as an ally of Sylas than with most other typical builds. In fact, Kassadin boasted an average winrate of 48.8% when synergizing his build and playstyle to Sylas with these items in his kit.
To have the best chance of coming out on top against your oponents, you should equip the First Strike, Magical Footwear, Future's Market, Cosmic Insight, Sudden Impact, and Ultimate Hunter runes from the Inspiration and Domination rune sets. Out of all the rune builds players picked for this champion pairing, this order of runes yielded the top win rate. In fact, these runes averaged a 48.8% win rate overall.
By default, tips, statistics, and builds on how to pair Sylas with Kassadin are presented for all ranked divisions. If you want to filter the stats and builds to a distinct division, you should use the selection menu at the top of this page.