- Script
- Roy Thomas (credited)
- Pencils
- Werner Roth (credited as Jay Gavin)
- Inks
- Dick Ayers (credited)
- Colors
- ?
- Letters
- Artie Simek (credited)
- First Line of Dialogue or Text
- The scene: the fantastic Danger Room in X-Men HQ...
- Genre
- superhero
- Characters
- X-Men: Angel [Warren Worthington III]; Beast [Hank McCoy]; Cyclops [Scott Summers]; Iceman [Bobby Drake]; Marvel Girl [Jean Grey]; Professor X [Charles Xavier]
Vera Cantor (guest); Colosso (first appearance); Count Nefaria [Luchino Nefaria] (villain); Eel [Leopold Stryke] (villain); Zelda Kurtzberg (guest); Plant Man [Samuel Smithers] (villain); Porcupine [Alexander Gentry] (villain); Scarecrow [Ebenezer Laughton] (villain); Unicorn [Milos Masaryk] (villain); Maggia
- Universe
- Marvel : mainstream
- Synopsis
- Trying once again to take a vacation, the X-Men are individually drawn to Central Park where they encounter phantom versions of themselves. One by one, they fall to five super powered villains. The X-Men are brought to Count Nefaria's fortress and he tries to convince them to join his plot to steal Washington D.C. and hold it for ransom.
- Reprints
- in Thor and the X-Men (Marvel UK, 1983 series) #21
- in Fantastic! (IPC, 1967 series) #42 (2 December 1967), #43 (9 December 1967)
- in Strange (Editions Lug, 1970 series) #22 (5 octobre 1971)
- in X-Men Annual (Marvel, 1970 series) #2 (November 1971)
- in Spidey (Editions Lug, 1979 series) #38 (10 mars 1983)
- in Thor and the X-Men (Marvel UK, 1983 series) #20 (August 31 1983)
- in Marvel Special (Marvel Italia, 1994 series) #10 (Aprile 1997)
- in Essential Uncanny X-Men (Marvel, 1999 series) #1 (September 1999) [black and white]
- in Marvel Masterworks: The X-Men (Marvel, 1998 series) #[3] (January 2002)
- in Essential Uncanny X-Men (Marvel, 1999 series) #1 [Third Printing] (2003) [black and white]
- in The X-Men Omnibus (Marvel, 2009 series) #1 ([April] 2009)
- in Marvel Masterworks: The X-Men (Marvel, 2009 series) #3 (2011)
- in X-Men Epic Collection (Marvel, 2014 series) #1 - Children of the Atom (2014)
Continued in The X-Men (Marvel, 1963 series) #23.
- Script
- Roy Thomas
- Pencils
- Werner Roth (illustrations)
- Inks
- Dick Ayers (illustrations)
- Colors
- ?
- Letters
- typeset
- Reprints
Letters from: Walter Willis III, Walt Smith, Dean Crawford, Don Feese, A. George Resciniti, Dexter Musgrove, Christine Cassello, Jim Eastabrook, and Francisco Cayse; M.M.M.S. entry form; "Next Ish" text.