Descent is a first-person shooter (FPS) game developed by Parallax Software and released by Interplay Productions in 1995 for MS-DOS, and later for Macintosh, PlayStation, and RISC OS. It popularized a subgenre of FPS games employing six degrees of freedom and was the first FPS to feature entirely true-3D graphics. The player is cast as a mercenary hired to eliminate the threat of a mysterious extraterrestrial computer virus infecting off-world mining robots. In a series of mines throughout the Solar System, the protagonist pilots a spaceship and must locate and destroy the mine's power reactor and escape before being caught in the mine's self-destruction, defeating opposing robots along the way. Players can play online and compete in either deathmatches or cooperate to take on the robots.
Descent was a commercial success. Together with its sequel, it sold over 1.1 million units as of 1998 and was critically acclaimed. Commentators and reviewers compared it to Doom and praised its unrestrained range of motion and full 3D graphics. The combination of traditional first-person shooter mechanics with that of a space flight simulator was also well received. Complaints tended to focus on the frequency for the player to become disoriented and the potential to induce motion sickness. The game's success spawned expansion packs and the sequels Descent II (1996) and Descent 3 (1999).
Gameplay
Single-player
thumb|250px|left|Screenshot of the player engaging a robot from a cockpit perspective. The yellow number and adjacent bars in the HUD represent the amount of total energy. Also in the HUD, counterclockwise from top left: the available [[Extra life|extra lives, an enemy missile lock indicator, a colored key inventory, the selected primary weapon, the player ship's shields, the selected secondary weapon, and the score count.]]
Descent is a first-person shooter and shoot 'em up The ship respawns at the start of the level at the cost of a life and the player can return to the area of the demise of their previous ship to recover these power-ups. The story begins with a briefing between PTMC executive S. Dravis and the player's character, PTMC's best "Material Defender", who is hired on a mercenary basis to eliminate the threat of a mysterious alien computer virus infecting the machines and robots used for off-world mining operations.
The PTMC developed numerous mines in the Solar System's planets and moons for a variety of uses, including resource extraction, science research, and military installations. Prior to entering a mine, the player receives an intelligence briefing upon the robots used there, however the computer virus has resulted in some existing robots either modified considerably or even new robots being produced that PTMC is unaware about. The player starts with the mines on the Moon and later shift to Venus and to Mercury, where a boss robot has to be destroyed. Afterward, the mines progress further away from the Sun, as the player visits Mars, then the moons of Jupiter, Saturn, Uranus, Neptune, and eventually to Pluto and its moon Charon. The player accesses the three secret levels located in the asteroid belt using alternative exit doors hidden in specific levels.
After defeating the boss robot on Charon, the Material Defender is informed he cannot return to the PTMC's headquarters in Earth orbit, as there is a chance his ship may be infected with the same virus as the defeated robots. His employer also mentions that PTMC has lost contact with their deep-space installations outside the Solar System, setting the stage for the sequel.