Kakusei Ky, which means "Awakened Ky" in Japanese, is an awakened EX version of Ky Kiske that only appears in Guilty Gear Isuka. He is one of two bosses in its GG Boost Mode, the other being Kakusei Sol.
Kakusei Ky uses a blue awakening power coupled with a permanent Dragon Install-like effect, infinite Tension and impressive Lightning techniques. Defeating Kakusei Sol and Kakusei Ky on the last stage of GG Boost mode unlocks Zako 1, 2, and 3.
In order to unlock him, the player must first have Ky's EX version unlocked by beating Arcade Mode. Playing Boost of Scramble as Robo-Ky II in RKII Factory Mode on at least Normal difficulty, one must defeat Kakusei Sol and Ky in Stage 5-E (Last Dance) with 1,400,000 points or more and not have used any warp points. One must then choose not to return to the factory and a giant Robo-Ky II ("Robo-Ky II Substance") will appear. Defeating it unlocks Kakusei Ky and Sol.
To select him, the player must simply highlight Ky Kiske on the Character Select Screen and press Start twice.
Kakusei Ky normally has a moveset mirroring Ky's EX moveset along with the return of Robo-Ky's old Ray Divider and Aces High attacks, albeit modified. Ky also in this state also has an unnamed version of Sacred Edge akin to Kakusei/Bousou Sol's new Overdrive.