The Flash's Mirror Master Arc Came To A Colorful Ending, But What Does It Mean?
CinemaBlend The Flash finally ended its Mirror Master (or Monarch?) arc, and while the episode brought lots of unexpected moments like the return of the original Ralph Dibny, and Iris West temporarily gaining powers, no twist could hold a candle to that ending scene. Granted, we're still not entirely sure what that final scene meant, though a current theory is exciting. To recap what happened, viewers of The Flash were taken back to the previous scene in which Iris and Barry's love brought back the original Speed Force. As sweet and slightly corny as that was, it's what happened afterward...
Source: cinemablend.com