First-Person Shooter-Z (FPS-Z, FPS+Z, or simply FPSZ) is a sub-genre of first-person shooters that emphasizes player movement in the Z-axis through the use of jetpacks or other similar device.
The term FPS-Z was first coined sometime around 2006 of 2007 by former Tribes Vengeance: Renegades and Ascension developer Rooster128 to help differentiate games like Tribes from other first-person shooters. FPS-Z's are essentially the same as first-person shooters, with the obvious emphasis on movement in the Z axis. Generally FPS-Z's are played in the first-person perspective, but some do include an optional third-person view. Though not the first, many consider the Tribes franchise to be the quintessential and most successful FPS-Z series. While many games before and after included elements of Z-axis movement, the Tribes series completely revolves around this aspect. Although they feature the same freedom of movement, FPS-Z's shouldn't be confused with six degrees of freedom(6DoF) games. These include space combat and simulation games such as Freespace, Freelancer, and Eve Online.
When dealing with Arena shooters such as Quake there's a bit of a grey area, since while players can easily propel themselves through the air by using rocket jumps or other similar mechanics, it's hard to say whether or not there's emphasis in this kind of movement when compared to a game like Tribes: Ascend. Instead of outright saying a game is or isn't an FPS-Z, it may be better to use a scale of sorts to measure the 'amount' of emphasis in the Z-axis.
In 2001 Sierra released Tribes 2, the sequel to Starsiege: Tribes. Although movement was a bit different, overall it was very similar to the first game and featured the standard Spinfusor, chaingun, and blaster, along with new weapons. It originally included clan and player profiles, along with email, chat, league tables, tournaments and message board functionality all within the game client. In 2002 Sierra released Tribes: Aerial Assault for the PlayStation 2, the first and only Tribes game for a console. It is essentially Tribes 2 ported to the PlayStation 2, and included online multiplayer.
In October of 2004 VU Games released Tribes: Vengeance. While it was met with mixed reactions from the community, it garnered generally positive reviews from the industry. Along with the usual multiplayer modes such as Capture the Flag and Arena, Vengeance also included a complete single-player campaign, the only Tribes game to include one.
In 2008 GarageGames released Fallen Empire: Legions, a browser-based "spiritual successor" to the Tribes franchise. Like Tribes, movement is based almost entirely around the use of jetpacks. Players are able to either take flight for a few seconds or glide across maps over a cushion of air, essentially replicating the skiing functionality found in Tribes games.
In September of 2009 SouthPeak Interactive released Section 8, which equipped all players players with a jet-pack. It included 32 online multiplayer support, custom load-outs and character customization. The game received mostly average to mixed reviews, with its low server population being the main drawback. In November 2009 Futuremark Games Studio released Shattered Horizon, a zero-gravity multiplayer-only FPS-Z that placed players in the broken remains of Earth's orbital infrastructure and hollowed-out asteroids. It featured 32 multiplayer online support and complete freedom of movement. While it received generally positive reviews, it required a fairly high-end computer which limited its player base.
In December 2009, a mod for Crysis was released as a public beta. The mod, titled MechWarrior Living Legends, allowed players to control battlemechs, while also giving players movement in the Z-axis through short bursts of energy. In March of 2010, a mod for Enemy Territory: Quake Wars called Tribal Wars was released and aimed at bringing back some of the gameplay elements found in Starsiege: Tribes, such as jetpacks, skiing and similar weapons.
In 2011 Hi-Rez Studios started the closed beta stage for Tribes: Ascend, which was then released in April 2012. Like previous Tribes titles, it too featured skiing, jetpacks, large outdoor maps and popular game modes such as CTF, TDM, and Arena. Like Tribes: Vengeance, game critics praised Ascend and gave it high marks, though the game received mixed reactions from seasoned Tribes players.
Not long after the release of Tribes: Ascend, a number of community-developed FPS-Zs started to emerge. Project Freefall technically started development during Ascend's closed beta by Cameron West, also known as Ignorance or Saccaed. Development on Project Freefall started in early 2012 originally on Unreal Engine 3, and was briefly ported to Unity before switching back after Unreal Engine 4 was released. Freefall features both skiing and jetpacks, and aims to be very open to modders. Each public build also comes with its source code for those interested.
Former Tribes player and Ascension developer Rooster128 revealed Project Teamsky in early 2013. Early videos showed a game similar to Tribes, at least from a movement-standpoint. While not much information regarding Project Teamsky has emerged, Rooster128 recently shared new images on the project's forum.
Also in early 2013 saw the early development stages of Legacy FPS, or Legacy, by another Tribes player known as SmoothP. Developed using Unity, Legacy mainly focused on creating a stand-alone version of the popular Tribes 2 game mode Team Rabbit 2. While the game saw a brief duration of popularity within the Tribes community, ultimately development slowed down to a point where the community lost interest and moved on. Developer SmoothP showed interest in continuing development as late as April 2014, however no updates have been released since then.
Project Z started development sometime during 2013 by former Legions: Overdrive developers, who now go by Archetype Studios. While the project originally began as a port of Legions: Overdrive to Unity in 2012, it eventually grew into its own separate game roughly a year later. As their website states, Tribes and Legions players will feel at home since Project Z will emphasize freedom of movement and a focus on competitive and casual team play. Currently the game is still under development, and recently revealed their website and first concept art to the public. It had its first public showing at PAX Prime 2014 in Seattle, WA on August 30, 2014.