Complex sentence: Brix and Bora on Earth-999 killing a cat with Spider-Man's powers; and Daimos killing Earth-7831 Spider-Man and all the animalistic residents of Counter-Earth.
Split into simpler sentences: Brix and Bora are on Earth-999 killing a cat with Spider-Man's powers. Daimos is on Earth-7831 killing Spider-Man and all the animalistic residents of Counter-Earth.