Dimension of the Past

Dimension of the Past (called "DOPA" for short) is an add-on episode for Quake developed by MachineGames, to commemorate the game's 20th anniversary. It's available to download for free, and was also included in the modern Quake port.

Despite not being developed by id Software themselves, the episode is officially released in the 2021 release, being developed by a fellow Zenimax-owned company that has previously co-operated with id Software as well as Nightdive Studios. The episode also contains many allusions and callbacks to Quake proper, such as the re-appearance of the Dopefish easter egg, along with the final level of the episode being almost identical to Shub-Niggurath's Pit.

It is the fourth episode (third 'expansion') in the Quake Remaster release (following Quake Mission Pack 2: Dissolution of Eternity), and is followed by the newest episode, Dimension of the Machine.

Levels

 * Dimension of the Past (difficulty selection)
 * The Military Base
 * The Power Supply
 * The Dark Days
 * The Forgotten Castle (secret level)
 * The Catacombs
 * The Stronghold
 * The Underworld
 * The House of Doom (secret level)
 * The Otherworld
 * The Year Zero

Deathmatch Maps

 * The Theater of Doom