Tip
Be careful to not on take Kai’sa’s Icathian Rain (Q)’s full damage by yourself, and try to avoid her Void Seeker (W) as well! Kai’sa will try to close in with Supercharge (E), so keep her in check with your longer range while raising your mist stacks with basic attacks and Piercing Darkness [Q]!
Senna vs Kai'Sa



