After Killing My Girlfriend at the Beginning, I Evolved into the Corpse King

[Apocalypse + Zombie Evolution + Not the Holy Mother + No System + Decisive Killing] What kind of exciting world would it be if zombies were ranked according to their eye color? The zombie levels from low to high are white, black, yellow, orange, blue, green, purple, red, and gold. Corresponding to the superpower training levels F, E, D, C, B, A, S, SS, SSS respectively. Then please follow the protagonist's footsteps and enter the door of the new world, and witness the rise of the zombie clan led by the protagonist.