| Issue | #25 |
| Published | October 1966 |
| Cover Price | 0.12 |
| Pages | 36 |
| Editing | Stan Lee |
| Notes | Pencil credits from Rich Donnelly via the GCD Error List. Original indexer credited Werner Roth. |
| Characters | The X-Men [Beast, Iceman, Cyclops, Angel]; Kukulcan |
| Genre | superhero |
| Pencils | Jack Kirby |
| Inks | Dick Ayers |
| Letters | Sam Rosen |
| Notes | Pencil credits from Rich Donnelly via the GCD Error List. Original indexer credited Werner Roth. |
| Characters | The X-Men (Professor X, Cyclops, Marvel Girl, Angel, Beast, Iceman); V: El Tigre (I; O; aka Kukulcan) |
| Genre | superhero |
| Script | Roy Thomas |
| Pencils | Werner Roth |
| Inks | Dick Ayers |
| Letters | Sam Rosen |
| Notes | Continued in X-Men 26 |
| Reprinted | in X-Men (Marvel, 1963 series) #73; in Marvel Special (Marvel Italia, 1994 series) #10 |