You can use Comet of Legend's flight to grow Starsurge to massive proportions.
Comet of Legend allows you to move quickly around the map; use it to put pressure on other lanes.
Save Voice of Light to use as a defense against melee opponents if you need to - otherwise, use its slow to start a fight at long range.
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 Aurelion Sol 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, Aurelion Sol 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 negative change shows that Kai'Sa helps Aurelion Sol perform not as well in competitive LoL games. Yet, the small difference demonstrates that this performance change is not very impactful.
When Aurelion Sol plays on the same team as Kai'Sa, he observes a small increase in his full damage dealt. This could indicate that Kai'Sa supports by providing protection for him to deal more damage or that her allyship also helps extend the game's duration. Similarly, when Aurelion Sol is played alongside Kai'Sa on the same team, he usually scores many fewer killing sprees compared to when he plays on his own. This is contrasting evidence that he is worse when playing with Kai'Sa.
Moreover, when Aurelion Sol plays with Kai'Sa on the same side, he on average receives a little more damage than when he fights alone. Taking more damage could indicate that Kai'Sa does a poor job of protecting Aurelion Sol during team fights.
There is no perfect ally for Aurelion Sol that will 100% of the time be his #1 ally. Yet, overall, Kai'Sa is a very bad companion for Aurelion Sol. By locking into the same team as Aurelion Sol, she drops their win rate by -3.7% to 46.9%. This signals that there is an easy to overcome and exploit synergy between Aurelion Sol and Kai'Sa that results in them performing worse together than alone.
Kai'Sa has a lower difficulty than Aurelion Sol. That means you don't need to be careful when lining up Kai'Sa comrades to fight alongside, as they will need a relatively low level of skill to play well with you.
Playing cooperatively, Aurelion Sol players will likely observe an overall large increase in your team’s capability to to do a lot of AP damage. Combined, these two can deal quite a lot of AP type damage.
Conversely, by pairing Aurelion Sol and Kai'Sa together, you may not be granting your team much utility. Plan to include other champs on your team that offsets this hole in this pairing's abilities.
Regardless of the skill of your Kai'Sa teammate, you need to focus on maximizing your gold income, outlasting your enemies, and clearing objectives. If you do this, you should do well, regardless.
To truly master Aurelion Sol in order to pair well with Kai'Sa during both the lane and mid / late game phases of League matches, you should keep reading to master a few extra lessons on this champion pairing. If you mind the build and stats presented here, you should grow your win rate by a lot.
The top finished items to have in your Aurelion Sol and Kai'Sa synergy build include Banshee's Veil, Rylai's Crystal Scepter, and Liandry's Torment. When Aurelion Sol combined at least these three finished items in his build, he did much better when paired up with Kai'Sa than with many other typical builds. In fact, Aurelion Sol had an average win rate of 46.9% when playing alongside Kai'Sa with these items in his kit.
To have the highest chance of crushing your oponents, you should equip the Arcane Comet, Manaflow Band, Transcendence, Gathering Storm, Magical Footwear, and Minion Dematerializer runes from the Sorcery and Inspiration rune sets. Of all the rune combinations players used for this team composition, this mixture of runes yielded the top win rate. In fact, these runes gave a 46.9% winrate overall.
If you would like to see Aurelion Sol with Kai'Sa collaboration tips and builds for a a specific division rank, feel free to choose one from the selection menu provided above. If viewing for the first time, the stats and build suggestions given are calculated using all matches with data with these champs.