Complex sentence: With several of his allies either victims of or collaborators with Superman's failed regime, Batman is forced to form a new team of superheroes to combat both the Society and the arrival of Brainiac, who puts Earth's entire existence at risk.
Split into simpler sentences: With several of his allies either victims of or collaborators with Superman's failed regime, Batman is forced to form a new team of superheroes to combat The Society. The situation is further complicated with the arrival of Brainiac, who puts Earth's entire existence at risk.