Justine Yeung/The CWAfter seven seasons of random musicals, a preposterous number of serial killings, and the epic highs and lows of high school football, Riverdale is coming to an end.The series has gone through many transformations in its run. It began as a stylistic murder mystery—the answer to the question, “What if we made the Archie comics dark and sexy?”—and then evolved into a slasher series in Season 2. In Season 3, it became a pseudo-supernatural cult drama, and then a full-on fantasy