The first edition, the Basic Set, was a box set priced at $15 and included the following:
- 16 page Battle Book which featured original art by Al Milgrom
- 52 page Campaign Book which featured original art by Sal Buscema
- Day of the Octopus game adventure
- a 2-sided map of New York City
- 8 character cards
- 25 cardboard tokens
TSR's gaming publication, Dragon magazine, had a monthly column called The Marvel-phile which usually added new characters or groups
Here's list of the Adventure modules that were released for the basic set:
- The Breeder Bombs (X-Men)
- Time Trap (Avengers)
- Murderworld! (Fantastic Four)
- Lone Wolves (Daredevil, Black Widow, Power Man, Iron Fist)
- Cat's Paw (Alpha Flight)
- Judge's Screen
- Avengers Assembled!
- Adventure Foldup Figures
- Pit of the Viper (incl. Adventure Foldup Figures)
- Secret Wars
- The Last Resort (West Coast Avengers)
- Thunder over Jotunheim (Thor)
- Fault Line (Spider-Man & Avengers)
- Project Wideawake
- Concrete Jungle
- Weapons Locker
- Gates of What If ? (Spider-Man, FF, Avengers)
Here's a review (a bit biased of course) of the game system by Marvel Age: