Veigar is extremely Mana and Cooldown Reduction dependent. Try buying items with these stats in order to increase the effectiveness of your passive and Baleful Strike.
Veigar is very fragile. It is valuable to select at least one summoner spell that can be used defensively.
Use Event Horizon to increase your chances of landing Dark Matter.
Make sure to buy items that will evolve at least 1 or 2 of your spells.
Work with your teammates to set up your Ultimate and optimize damage with your passive.
Try to catch enemy carries alone to burst them with Icathian Rain.
The Veigar Kai'Sa synergy stats shown here demonstrate the areas of his gameplay that do better (or worse) when paired with Kai'Sa, compared to his overall stats. Significant differences are areas of focus that highlight how his gameplay changes when paired with this other champion.
Overall, Veigar sees a very large drop in his KDA (ratio of kills and assists to deaths) when paired with Kai'Sa. His KDA worsened from NaN to NaN. This worsening shows that Kai'Sa helps Veigar perform worse in ranked LoL rounds. Yet, the small difference demonstrates that this performance change is only marginal.
When Veigar tries to synergize with Kai'Sa, he gets a barely noticable drop in his complete damage output. This difference could indicate that Kai'Sa does not provide cover for him to deal more damage or that her support also helps extend the game's duration. Similarly, when Veigar is played with Kai'Sa 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 with Kai'Sa.
Additionally, when Veigar plays with Kai'Sa on the same team, he on average receives a little less damage than when he plays alone. Receiving not as much damage could mean that Kai'Sa does a decent job of protecting Veigar in teamfights.
There is no universally accepted best synergy for Veigar that will 100% of the time be his #1 ally. However, overall, Kai'Sa is a relatively poor ally for Veigar. By locking into the same team as Veigar, she drops their win rate by -1.6% to 47.7%. This shows that there is a bad synergy between Veigar and Kai'Sa that results in them performing worse together than without each other.
Kai'Sa has a lower difficulty than Veigar. That means you don't need to be careful when enlisting Kai'Sa allies to fight alongside, as they will require a lower level of skill to cooperate well with you.
Working alongside, you should witness an overall large increase in your team’s capability to deal magic damage. Combined, these champs are able to dish out a surprising amount of magic type damage.
In contrast, by aligning Veigar and Kai'Sa together, you may not be granting your team enough tankyness. Make sure to have other champions on your team that nullifies this relative disparity in this pairing's potential.
Regardless of the ability of your Kai'Sa ally, you need to focus on maximizing your income, warding to avoid ambushes, and taking down objectives. If you follow these simple suggestions, you should do well, regardless.
If you would like to truly master Veigar in order to synergize with Kai'Sa during both the laning and mid / late game phases of League rounds, you should continue reading to learn a few extra tricks and insights into this champion pairing. If you listen to the build and stats presented here, you should increase your win rate by a lot.
The best items to focus on in your Veigar and Kai'Sa synergy build include Seraph's Embrace, Rabadon's Deathcap, and Stormsurge. When Veigar bought at least these three items in his build, he did a lot better as an ally of Kai'Sa than with many other commonly used builds. In fact, Veigar boasted an average win rate of 47.7% when playing alongside Kai'Sa with these items in his kit.
To have the highest probability of coming out on top against your oponents, you should equip the First Strike, Magical Footwear, Biscuit Delivery, Cosmic Insight, Manaflow Band, and Transcendence runes from the Inspiration and Sorcery rune sets. Of all the rune combinations players used for Veigar and Kai'Sa pairings, this set of runes yielded the best win rate. Moreover, these runes averaged a 47.7% win rate overall.
By default, tips, statistics, and builds on how to synergize Kai'Sa with Veigar are shown for all ranked divisions. If you want to scope the statistics and builds to a specific rank, you may use the selection menu earlier in the counter matchup guide.