Complex sentence: Ra's al Ghul is one of Batman's most enduring enemies and belongs to the collective of adversaries that make up Batman's rogues gallery, although his high status as a supervillain has also caused him to come into conflict with other superheroes in the DC Universe.
Split into simpler sentences: Ra's al Ghul is one of Batman's most enduring enemies and belongs to the collective of adversaries that make up Batman's rogues gallery. Given Ra's al Ghul's high status as a supervillain, he also comes into conflict with other superheroes in the DC Universe.