Complex sentence: Subsequently, Grodd conquers Earth, having used his mental abilities to control the minds of every remaining inhabitant of the planet except Batman, that resist using his concentration abilities, but this is broken when Alfred Pennyworth dies enabling Grodd capture him.
Split into simpler sentences: Subsequently, Grodd conquers Earth, having used his mental abilities to control the minds of every remaining inhabitant of the planet except Batman, that he resists using his concentration abilities. This is broken when Alfred Pennyworth dies enabling Grodd capture him.