Tales to Astonish (1959) #13

The First Appearance of Groot! Before becoming a Guardian of the Galaxy, Groot was a terrifying monster from Planet X. Possessing a vocabulary larger than "I am Groot", Groot's Marvel Monster origins are revealed here!
Published: 11/1/1960
- Dick Ayers, inker
- Steve Ditko, inker
- Don Heck, inker
- Jack Kirby, penciler
- Stan Lee, writer
- Larry Lieber, writer
- Art Simek, letterer