In 1987, beginning with issue #55, she became the "New Mutants" scripter. Similarly to "X-Factor", she was originally brought in as a fill-in writer so that Chris Claremont could launch two other titles, but ended up writing the series for three and a half years, ending with #97 in 1991. It was during this run that she and artist Rob Liefeld introduced Cable, another important character in the X-Men franchise. In 1988–89, she and her husband co-wrote the "Havok and Wolverine: Meltdown" limited series painted by Jon J Muth and Kent Williams.