Wolfenstein 3D

Wolfenstein 3D (also written Wolfenstein 3-D) is a first-person shooter created by id Software and published by Apogee Software in 1992. It involves the adventures of an Allied soldier, B.J. Blazkowicz, fighting his way through a series of Nazi dungeons during World War II. It owes much of its success to an aggressive shareware marketing campaign which was later repeated with even greater success for Doom. It also spawned a commercial prequel, Spear of Destiny, which used the same engine. Since then several Wolfenstein games have been made on newer tech.

Inspiration for this game came from the even older 2D games Castle Wolfenstein and Beyond Castle Wolfenstein, published by Muse Software. Unlike these predecessors, Wolfenstein 3D shifted the focus away from puzzle solving in favor of more action-oriented gameplay. Though id had planned to include more strategic elements seen in these earlier games (such as wearing captured uniforms and dragging bodies), these features made gameplay too complex, slowing the action down. The final release did retain some arcade-style concepts, such as lives and scoring.

Technical
The engine is fairly simple, using maps composed of tiles, which only allow 90-degree angles between walls. Planes are shaded with flat colors instead of having textures. Much of the source code for Wolfenstein 3D was later reused in Apogee's Rise of the Triad, released in 1995. Like the Doom engine, the Wolfenstein 3D engine was also used for several other games; Blake Stone: Aliens of Gold, Blake Stone: Planet Strike, Corridor 7: Alien Invasion, and Operation Bodycount, which enhance the engine with numerous features, some similar to those ID added to Doom such as textured planes, distance shading, teleporters and switches.

Fanbase
At the time of its release, Wolfenstein 3D was seen as a revolutionary new product, and is regarded by many to be the grandfather of all FPS games, as it popularized the genre tremendously. It is especially noteworthy for having directly led to the development and publication of Doom just a year after its release. Although Doom and its successors quickly superseded Wolfenstein to become an equally important milestone in the development of the first-person shooter, Wolfenstein still enjoys a substantial following on the Internet, including websites, user-created maps, and even totally new games based on the source code, which was released on July 21, 1995.

Similarities with Doom engine games

 * The style of game divided in episodes is very similar to Wolfenstein. Initially, Wolfenstein had three episodes, each with nine levels and a secret level. Later on, the expansion pack "The Nocturnal Missions" with three new episodes was added. Doom had three episodes originally, with eight levels and a secret level each, and an expansion pack with a new episode was also released. Both games have a boss at the end of each episode. Both shareware versions include only the first episode.
 * The first episode of Doom contains only a couple of weak opponents, and in the end there is a boss that is supreme in comparison with them. This resembles Wolfenstein's gameplay style. However, later episodes of Doom include more powerful weapons and enemies, and the bosses are much more powerful than any enemy.
 * The second Wolfenstein game, Spear of Destiny, includes 19 new levels and two secret levels in a single campaign, and the episode select screen was removed. Doom II was released in a very similar way.
 * The status bar has the same style, including displays for health, ammo and keys. Early versions of Doom included displays for score and lives, and the selected weapon was also illustrated in the bar.
 * The supercharge power-up in Doom resembles the extra lives in Wolfenstein.
 * The status bar face is very similar to the one in Wolfenstein, including a grin face when the player picks up the chaingun. Spear of Destiny also had an Ouch Face and the face has golden eyes in god mode.
 * Wolfenstein has three weapons, the pistol, the machine gun and the chaingun, all which use the same ammo. Doom still kept the pistol and chaingun. However, instead of the machine gun, it included the shotgun which used a different set of ammo.
 * The ammo clip sprite of Doom is similar to that of Wolfenstein, and is also dropped by the most common type of enemy.
 * The Doom demons act almost exactly like the Wolfenstein dogs.
 * The chaingunner is somewhat reminiscent of the first Wolfenstein boss, Hans Grosse.
 * The chaingun carried by the Wolfenstein bosses looks similar to the spiderdemon's chaingun. The most clear similarity is that they both have six barrels.

Homages in Doom engine games

 * The swastika room of E1M4: Command Control (removed in version 1.4 and subsequent revisions).
 * The SS Nazi monster, based on the same enemy in Wolfenstein 3D.
 * The two secret levels, which are recreations of E1L1 and E1L9. Instead of attack dogs, brown-uniformed foot soldiers, and Hans Grosse, the player encounters Demons, the SS Nazi troopers, and a Cyberdemon respectively. The secret levels also include music from Wolfenstein 3D and Spear of Destiny.