The creative team on Doctor Doom was initially composed of writer Roy Thomas and penciler-inker Wally Wood, a veteran of classic 1950's EC Comics stories and one of the early, signature artists of Daredevil. Wood remained as artist through issue #4 (Feb. 1971), succeeded by penciler George Tuska for two issues and Gene Colan for the final two. Larry Lieber was writer for #3-6, succeeded by Gerry Conway.
Ka-Zar was initially by the team of writer and Marvel editor-in-chief Stan Lee and penciler and co-plotter Jack Kirby, the duo who had introduced the jungle lord years before as a one-issue supporting character in The X-Men. Ka-Zar had since guest starred in Daredevil and in other series before gaining his first solo feature here. After that initial story, Roy Thomas scripted the second installment, with the team of writer Gerry Conway and penciler Barry Windsor-Smith taking over for issues #3-6. Thomas and signature Hulk artist Herb Trimpe teamed for the next two issues, with Thomas abetted by Mike Friedrich on the latter. Astonishing Tales then starred Ka-Zar solely in stories ranging from 16 to 21 pages each.
A variety of creative teams followed, with Lee, Thomas, Conway, and Len Wein individually writing or collaborating on stories before Mike Friedrich became regular writer with issue #14 (Dec. 1972). Pencilers included Dan Adkins, Rich Buckler, Gil Kane, and John Buscema, plus a Buscema-Neal Adams collaboration one issue. The feature ended with #20 (Oct. 1973).
Issue #14 featured a censored color reprint of the black-and-white Ka-Zar tale in the comics magazine Savage Tales #1 (May 1971). Issues #12 and #13 introduced Man-Thing to color comics, as a Ka-Zar antagonist.
Two issues contained backup-feature reprints of 1950s jungle stories from Marvel predecessor Atlas Comics: Two stories from Lorna the Jungle Girl #14 (July 1955) in Astonishing Tales #9, and a Jann of the Jungle story from Jungle Tales #2 (Nov. 1954), in Astonishing Tales #14.
Issues #21-24 (Dec. 1973 - June 1974) featured "It! The Living Colossus", starring a stone giant introduced in an anthologicy science fiction-monster story in Tales of Suspense #14 (Feb. 1961), with a sequel in issue #20 (Aug. 1961). Tony Isabella and Dick Ayers comprised the modern feature's writer-artist team.
The final feature in Astonishing Tales introduced Deathlok, a conflicted cyborg who predated the popular movie character RoboCop by several years and has become one of the most enduring Marvel characters among those introduced in the 1970's. Created by artist Rich Buckler, who devised the initial concept, and writer Doug Moench, the feature ran from #25-28 & 30-36 (Aug. 1974 - Feb. 1975 & June 1975 - July 1976), the final issue. Bill Mantlo scripted issues #32-35, with Buckler himself scripting the finale.
Issue #29 (April 1975) was a fill-in that reprinted an edited version of the first Guardians of the Galaxy story, from Marvel Super Heroes #18 (Jan. 1969).