Having crash-landed on the planet Targ (en route to the Gamma System of Damocles), the player's main objective is to find a means of escape.

As well as providing assistance to the player, much of the humour within the games comes from the occasional sarcastic remarks made by Benson.

[2] The player explores a world rendered in realtime 3D graphics, completing a number of non-linear tasks in order to achieve a single main objective.

For instance, each faction seeks the destruction of installations belonging to its rival, and the capture of material or other resources to support their cause.

Instead, it is pink in the Amiga and Atari (8-bit and ST) versions,[3][4] dark blue on the Commodore 8-bit platforms (C64 and Plus/4)[5][6] and yellow on the ZX Spectrum.

[9][12] RUN reviewer Bob Sodaro noted the replay value of Mercenary for the Commodore 64, writing: "Prior to marking up the maps [included with the game], you should make a number of photocopies so you'll have clean copies when playing subsequent adventures".

It described the game's size and Atari 8-bit version's graphics as "awesome", but warned that a colour display was required.

[13] The ZX Spectrum version of Mercenary was voted number 15 in the Your Sinclair Readers' Top 100 Games of All Time.

[18] The program, called MDDClone (Mercenary, Damocles, Dion crisis Clone) is freeware, includes all three games, selectable through a drop-down list.

The graphics and gameplay are identical to the Atari ST version, with the additional option to fix some bugs that were originally present.