Complex sentence: He later rallies the rebels with Nubian leaders Balthazar and Queen Isis to stand up towards Memnon's tyranny, with Cassandra's help, he ultimately defeats Memnon as a defiance to her vision (where he is depicted as perishing).
Split into simpler sentences: He later rallies the rebels with Nubian leaders Balthazar and Queen Isis to stand up towards Memnon's tyranny. With Cassandra's help, he ultimately defeats Memnon in defiance of her vision (where he is depicted as perishing).