| Issue | #21 |
| Published | November 1984 |
| Cover Price | 1.00 USD |
| Pages | 52 |
| Editing | Ann Nocenti (editor); Jim Shooter (editor-in-chief) |
| Notes | Double-Sized Issue; Painted Cover; The newsstand version of this comic has a crazy scribbled $1.00 price drawn by Sienkiewicz. |
| Characters | Wolfsbane, Magik, Magma, Cannonball, Sunspot. |
| Genre | superhero |
| Pencils | Bill Sienkiewicz |
| Inks | Bill Sienkiewicz |
| Colors | Bill Sienkiewicz |
| Notes | Double-Sized Issue; Painted Cover; The newsstand version of this comic has a crazy scribbled $1.00 price drawn by Sienkiewicz. |
| Reprinted | in Nuovi Mutanti, I (Play Press, 1989 series) #17 |
| Characters | Professor X, Cannonball, Magik, Magma, Psyche, Sunspot, Wolfsbane; SC: Lockheed, Doug Ramsey, Warlock; GA: Magneto (from Marvel Graphic Novel #5; next: Uncanny X-Men #188). |
| Synopsis | The New Mutant girls host a slumber party with their friends from Salem Center; Warlock destroys Asteroid M and lands near Xavier's school; after some chaos, the New Mutants bring in Doug to communicate with Warlock, and invite him to join the school. |
| Genre | superhero |
| Script | Chris Claremont |
| Pencils | Bill Sienkiewicz |
| Inks | Bill Sienkiewicz |
| Colors | Glynis Wein |
| Letters | Tom Orzechowski and L. Lois Buhalis |
| Notes | Warlock joins the New Mutants at the end of this story, and Doug Ramsey shortly after. Magneto's long-time base, Asteroid M, is destroyed in this story; it is rebuilt in X-Men (1991) #1. The New Mutants appear next in New Mutants Annual #1. |
| Reprinted | in New Mutants: The Demon Bear Saga, The (Marvel, 1990 series) #[nn]; in Nuovi Mutanti, I (Play Press, 1989 series) #17 |
| Characters | Cannonball |
| Genre | superhero |
| Script | Chris Claremont |
| Pencils | Bill Sienkiewicz |
| Inks | Bill Sienkiewicz |
| Colors | Glynis Wein |
| Letters | Tom Orzechowski or L. Lois Buhalis |
| Reprinted | in Nuovi Mutanti, I (Play Press, 1989 series) #17 |
| Characters | Magik |
| Genre | superhero |
| Script | Chris Claremont |
| Pencils | Bill Sienkiewicz |
| Inks | Bill Sienkiewicz |
| Colors | Glynis Wein |
| Letters | Tom Orzechowski or L. Lois Buhalis |
| Reprinted | in Nuovi Mutanti, I (Play Press, 1989 series) #17 |
| Characters | Sunspot |
| Genre | superhero |
| Script | Chris Claremont |
| Pencils | Bill Sienkiewicz |
| Inks | Bill Sienkiewicz |
| Colors | Glynis Wein |
| Letters | Tom Orzechowski or L. Lois Buhalis |
| Reprinted | in Nuovi Mutanti, I (Play Press, 1989 series) #20 |