Complex sentence: After several attempts, he began to rethink his approach; however, Waverider accidentally came in physical contact with Captain Atom, unleashing a storm of temporal energy that opened a gate to the future through which Monarch emerged.
Split into simpler sentences: After several attempts, he began to rethink his approach. However, Waverider accidentally came in physical contact with Captain Atom, unleashing a storm of temporal energy that opened a gate to the future through which Monarch emerged.