Re: Rumoured New X Men Cartoon
Even the "one-parters" were tied to episodes from a previous season. Look at "Courage", where Morph returns the to X-Men after his rehabilitation and had to face the Sentinels again.
Or the episode where Nightcrawler discovers that Mystique is his mother, Rogue his sister, and Graydon Creed his brother. At the end Gradyon Creed was delivered to Sabretooth.
Or how about the episode when Rogue's boyfriend Cody returns as one of the Brood. Way back in episode 1, "Night of the Sentinels", Rogue explains that she first discovered she was a mutant when she kissed her boyfriend Cody which left him in a coma.