Theresa Cassidy

Theresa Maeve Rourke Cassidy is a fictional superhero who has gone by several code names including Siryn and Banshee. She is featured in comic book titles published by Marvel Comics and is associated with the X-Men line of titles. She first appeared as Siryn in Spider-Woman, Volume 1 #37 in April, 1981. She adopted her late father's former code-name Banshee in X-Factor, Volume 1 #200 in February, 2010. She then took on the alias of Morrigan, which she began using in X-Factor #244 in November, 2012.