The Challengers of the Unknown still open Adventure with the second part of the brand-new story started last issue, "Contract on a Champ!", by Bob Rozakis, George Tuska, and Andy Mushynsky.
Other stories include:
"Superboy's Big Brother" by Robert Bernstein and George Papp
Aquaman in "To Win Is To Lose" by Steve Skeates, Jim Aparo, and Dick Giordano
"Captain Marvel Faces Fear!" by William Woolfolk and Pete Costanza
"The Legion of Super-Villains" by Jerry Siegel, Curt Swan, and Sheldon Moldoff
The Spectre in "The Sinister Lives of Captain Skull" by Gardner Fox and Murphy Anderson
...plus the regular text-page feature about the Legion by Paul Levitz.
Because of the extra-long Superboy story, there is no seventh feature in this issue. As a kid, I remember being disappointed because I would've always rather read a Zatanna or Black Canary story than another Legion tale. Oh, well.
Covers by Keith Giffen and Frank Giacoia and Giffen and Romeo Tanghal.