Pitfall: the Mayan Adventure is a side-scrolling action platformer. It's the forth game in the Pitfall series. It was developed by Activision in partnership with Redline games and published by Activision in 1994.
MechWarrior 2: 31st Century Combat is a 3D vehicle combat sim game created by Activision and released in 1995 for MS-DOS. It was ported later to Windows and Mac, in addition to the console versions released in 1997.
Hunter is a 3D action-adventure created by Paul Holmes and published by Activision in 1991 for the Amiga and Atari ST. It is considered the first successful example of a "sandbox" video game based on free-roaming in a 3d environment.
Prophecy: the Fall of Trinadon is a single-player action RPG designed by Richard L. Seaborne and published by Activision in 1989 for the MS-DOS. In a world dominated by a tyrant named Krellane, wars and rebellions are commonplace.
Little Computer People is an incredibly advanced life simulation game created in 1985 by Activision for the Commodore 64, ZX Spectrum, Atari ST and Apple II. An Amiga version was released in 1987.
Pitfall II: Lost Caverns is the sequel to the award-winning PItfall by David Crane and was developed and published by Activision in 1984 for 9 different platforms including Apple II, Commodore 64, Colecovision and Atari 5200.
The Activision Decathlon, or simply Decathlon, is a sports simulation created by David Crane initially for the Atari 2600 and published in 1983. It was then ported to MSX, Colecovision, Atari 5200 and Commodore 64.