Kerrigan's attack speed increases by 10% … The Art of StarCraft II: Wings of Liberty, The Art of StarCraft II: Heart of the Swarm, Blizzard Cosplay: Tips, Tricks, and Hints, The BlizzCon Book: A Celebration of Our Community, StarCraft 2: Heart of the Swarm Preview Part 1 - Getting to Know the Swarm, Hands On With StarCraft II: Heart of the Swarm’s Campaign, Now With More RPG and Space Yetis, IGN: StarCraft II: Heart of the Swarm Pictures (PC) (Destruction Focus).
The fight with Kraith doesn't require any additional units, so if they die, it's not important. Starcraft II: Heart of the Swarm features Kerrigan as a hero character in nearly all of the missions.
