Complex sentence: Thanks to the controversy, and additional promotion by Island, over one million copies of "The Great Milenko" had been sold by 1998, and Insane Clown Posse was ready for the fifth Joker's Card, "The Amazing Jeckel Brothers".
Split into simpler sentences: Thanks to the controversy, and additional promotion by Island, over one million copies of "The Great Milenko" had been sold by 1998. It Insane Clown Posse was ready for the fifth Joker's Card, "The Amazing Jeckel Brothers".