An immersive sim (simulation) is a
video game genre
A video game genre is an informal classification of a video game based on how it is played rather than Computer graphics, visual or narrative elements. This is independent of setting (fiction), setting, unlike works of fiction that are expressed ...
that emphasizes player choice. Its core, defining trait is the use of
simulated systems that respond to a variety of player actions which, combined with a comparatively broad array of player abilities, allow the game to support varied and creative solutions to problems, as well as
emergent gameplay beyond what has been explicitly designed by the developer.
This definition is not to be confused with game systems which allow player choice in a confined sense or systems which allow players to easily escape consequences of their choices.
Immersive sims by definition allow for multiple approaches, and typically incorporate elements of multiple genres, including
role-playing games
A role-playing game (sometimes spelled roleplaying game, or abbreviated as RPG) is a game in which players assume the roles of characters in a fictional setting. Players take responsibility for acting out these roles within a narrative, eith ...
,
stealth,
first-person shooter
A first-person shooter (FPS) is a video game genre, video game centered on gun fighting and other weapon-based combat seen from a First person (video games), first-person perspective, with the player experiencing the action directly through t ...
s,
platform game
A platformer (also called a platform game, and sometimes a jump 'n' run game) is a subgenre of action game in which the core objective is to move the player character between points in an environment. Platform games are characterized by levels wi ...
s,
survival horror
Survival horror is a Video game genre, subgenre of horror games. Although combat can be part of the gameplay, the player is made to feel less in control than in typical action games through limited ammunition or weapons, health, speed, and visio ...
and
adventure game
An adventure game is a video game genre in which the player assumes the role of a protagonist in an interactive story, driven by exploration and/or puzzle-solving. The genre's focus on story allows it to draw heavily from other narrative-based m ...
s. Although they typically have smaller worlds than
open world
In video games, an open world is a virtual world in which the Gamer, player can approach objectives freely, as opposed to a world with more linear and structured gameplay. Notable games in this category include ''The Legend of Zelda (video game ...
games, they also generally allow for
open-ended gameplay, allowing the player to progress in any order and pursue side missions alongside any main story missions.
Immersive sims are generally compared to games developed by
Looking Glass Studios. The first such game generally considered an immersive sim is ''
Ultima Underworld: The Stygian Abyss'', and other early examples include ''
Thief'' and
''Thief 2'', ''
System Shock
''System Shock'' is a 1994 first-person action-adventure game, action-adventure video game developed by LookingGlass Technologies and published by Origin Systems. It was directed by Doug Church with Warren Spector serving as producer. The game ...
'' and ''
System Shock 2'', as well as the first ''
Deus Ex''.
The term "immersive sim" emerged in the 2000s and began to be used regularly in the second half of the 2010s, often applied retroactively to the earlier entries in the genre. It may also be used to describe the set of
game design
Game design is the process of creating and shaping the mechanics, systems, rules, and gameplay of a game. Game design processes apply to board games, card games, dice games, casino games, role-playing games, sports, Wargame (video games), war ga ...
principles behind the immersive sim genre, which uses interacting, reactive and consistent game systems to create emergent gameplay and a sense of player agency.
Concept
Immersive sims typically task the player to make their way through levels and complete missions, but do not enforce the means by which the player does this. A common example would be where the player-character must get past a guard. The choice of how to do this would be up to the player: they may attempt to sneak around; use
parkour
Parkour () is an athletic Training#Physical training, training discipline or sport in which practitioners (called ''traceurs'') attempt to get from one point to another in the fastest and most efficient way possible, without assisting equipment ...
or other similar abilities, aided with some equipment, to slip around them; find small passageways that allow them to get around the guard; create a distraction that draws the guard away from their post; convince or bribe the guard to ignore them; or simply attack and kill or disable the guard directly. The choices may be limited by the player-character's abilities and current inventory, and there may be consequences of the player's choice. For example, killing or disabling the guard could leave the guard's body to be found later, raising the alert level of other guards. However, this element of consequence can be seen as a negative to players if taken throughout the game. For example, ''
Dishonored'' introduced a "chaos" system that adjusted how enemy guards would behave based on how much violence and disturbance a player had used earlier in the game so as to encourage players to try different tactics to avoid making future encounters harder. This system was removed for ''
Dishonored: Death of the Outsider'', as well as the addition of optional quests to encourage alternate approaches to missions.
Warren Spector, part of
Looking Glass Studios, said that immersive sims create the feeling that "you are there, nothing stands between you and belief that you're in an alternate world".
Many of the key developers of immersive sims compare them to tabletop ''
Dungeons & Dragons
''Dungeons & Dragons'' (commonly abbreviated as ''D&D'' or ''DnD'') is a fantasy tabletop role-playing game (TTRPG) originally created and designed by Gary Gygax and Dave Arneson. The game was first published in 1974 by TSR (company)#Tactical ...
'' games hosted by a good
gamemaster, or to
live action role-playing game
A live action role-playing game (LARP) is a form of role-playing game where the participants physically portray their character (arts), characters.(Tychsen et al. 2006:255) "LARPs can be viewed as forming a distinct category of RPG because of ...
s, in that there are a set of rule systems to keep it a game, but the game will react to the players' actions rather than force the player to conform to a specific action.
Spector is credited with the term "immersive sim" in a
post-mortem
An autopsy (also referred to as post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode, and manner of death ...
he wrote on the development of ''Deus Ex'' in 2000,
although Spector himself attributes it to his Looking Glass colleague
Doug Church instead.
Mark Brown of the YouTube series ''
Game Maker's Toolkit'' identified that a key differentiating feature of immersive sims is that they do not readily use scripted or fixed events. Instead, they use a consistent series of rules and systems throughout the game. These consistent systems then can be exploited by the player to complete objectives in unique and unpredictable ways, with the game reacting to the player's decisions.
Brown uses the example of being able to fire rope arrows (to climb on) at any wooden surface in the original ''
Thief: The Dark Project'' (1998), while the 2014 ''
Thief'' game limited what locations these could be used, removing the immersive sim elements.
Rick Lane of ''
PC Gamer
''PC Gamer'' is a magazine and website founded in the United Kingdom in 1993 devoted to PC gaming and published monthly by Future plc. The magazine has several regional editions, with the UK and US editions becoming the best selling PC games m ...
'' noted that while earlier games in ''
The Elder Scrolls
''The Elder Scrolls'' is a series of action role-playing games, action role-playing video games primarily developed by Bethesda Game Studios and published by Bethesda Softworks. The series focuses on Nonlinear gameplay, free-form gameplay in an ...
'' series were not immersive sims, ''
The Elder Scrolls IV: Oblivion'' (2006) transitioned the series to an immersive sim.
History
Warren Spector considered ''
Ultima VI: The False Prophet'' (1990) the first game to have an immersive sim mentality as while played from a top-down view, it relied less on events and planned-out puzzles, and instead provided the rulesets and systems through its living world to allow players to craft their own solutions to situations. Spector described one playtesting example from ''Ultima VI'' that he considered the genesis of the immersive sim genre, in which a playtester lacked a magical spell needed by his party to pass by a closed gate, and instead used a pet mouse character to sneak through small spaces and access the necessary controls to open the gate, something none of the developers had anticipated.
''
Ultima Underworld: The Stygian Abyss'' (1992) is considered the first game to demonstrate the necessary elements of an immersive sim according to Spector and others.
It built upon ''Ultima VI''s gameplay and added in the first-person perspective, predating ''
Wolfenstein 3D
''Wolfenstein 3D'' is a 1992 first-person shooter game developed by id Software and published by Apogee Software and FormGen for DOS. It was inspired by the 1981 Muse Software video game '' Castle Wolfenstein'', and is the third installment ...
'', the game that first popularized
first-person shooter
A first-person shooter (FPS) is a video game genre, video game centered on gun fighting and other weapon-based combat seen from a First person (video games), first-person perspective, with the player experiencing the action directly through t ...
s, by a few months. The first-person view helped to cement the impression that the player was part of the game's world that they had full control of, and completing the impression of immersion.
Spector recalled that he had thought to himself "Do you not realize that the entire world just changed?" on seeing the initial demo for ''Ultima Underworld''.
Other early examples include ''
System Shock
''System Shock'' is a 1994 first-person action-adventure game, action-adventure video game developed by LookingGlass Technologies and published by Origin Systems. It was directed by Doug Church with Warren Spector serving as producer. The game ...
'' (1994) and its sequel ''
System Shock 2'' (1999), ''Thief: The Dark Project'' (1998) and its sequel ''
Thief II'' (2000), ''
Deus Ex'' (2000), and ''
Arx Fatalis'' (2002).
However, at the same time, more action-oriented games with strong narrative elements that followed from ''Wolfenstein 3D'', like ''
Doom'' (1993) and ''
Half-Life Half-life is a mathematical and scientific description of exponential or gradual decay.
Half-life, half life or halflife may also refer to:
Film
* Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang
* ''Half Life: ...
'' (1998), drew larger commercial sales, making it difficult to gain publisher interest.
In the late
2000s
File:2000s decade montage3.png, From top left, clockwise: The Twin Towers of the original World Trade Center (1973–2001), World Trade Center on fire and the Statue of Liberty on the left during the September 11 attacks, terrorist attacks on Sep ...
, several games emerged that revitalized interest in the immersive sim, including ''
The Elder Scrolls IV: Oblivion'' (2006), ''
BioShock'' (2007), ''
S.T.A.L.K.E.R.: Shadow of Chernobyl'' (2007) and ''
Fallout 3'' (2008).
Spurred from these successful titles, there have been new titles in the ''Deus Ex'' series (''
Deus Ex: Human Revolution'' (2011), ''
Deus Ex: Mankind Divided'' (2016)), the ''Underworld'' series (''
Underworld Ascendant'' (2018)).
The genre's popularity continued with major releases from
Arkane Studios
Arkane Studios SASU is a French video game developer based in Lyon. It was founded in 1999, and released its first game, ''Arx Fatalis'', in 2002. The studio has created the popular Dishonored (series), ''Dishonored'' series as well as developi ...
(''
Dishonored'' (2012), ''
Prey
Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not ki ...
'' (2017) and ''
Deathloop'' (2021)). White Paper Games' ''
The Occupation
''The Occupation'' is a single-player adventure video game developed by White Paper Games and released on PlayStation 4, Xbox One, and Microsoft Windows on 5 March 2019. The game takes place in a single government building, in real-time over f ...
'' (2019) and
WolfEye Studios' ''
Weird West'' (2022), were developed acknowledging the design principles of immersive sims.
Other titles in this period, such as the ''
Hitman
Contract killing (also known as murder-for-hire) is a form of murder or assassination in which one party hires another party to kill a targeted person or people. It involves an illegal agreement which includes some form of compensation, moneta ...
'' series, and ''
The Legend of Zelda: Breath of the Wild'' (2017) and its sequel ''
Tears of the Kingdom'' (2023), while not necessarily considered immersive sims, have been said to possess elements of the genre, given their "sufficiently advanced
physics engine
A physics engine is computer software that provides an approximate simulation of certain physical systems, typically classical dynamics, including rigid body dynamics (including collision detection), soft body dynamics, and fluid dynamics. I ...
/systems that interact with both player verbs and mechanics and level design" and emphasis on player freedom and emergent gameplay.
Performance in the industry
While the immersive sim genre is well-received critically, its performance within the
video game industry
The video game industry is the tertiary industry, tertiary and quaternary industry, quaternary sectors of the entertainment industry that specialize in the video game development, development, marketing, distribution (marketing), distribution, ...
tends to be poor and sales of immersive sim games have been varying. The original ''Deus Ex'' sold more than 500,000 units (at the time, a respectable number) but its immediate sequel, ''
Deus Ex: Invisible War'' was considered a commercial failure. More recently, while ''
Deus Ex: Human Revolution'' sold more than 2.1 million copies within a month of its release, its sequel ''
Deus Ex: Mankind Divided'' had not yet cleared one million in sales a year after its release.
''
Dishonored 2'' also did not see a sales uptake similar to the one the original ''Dishonored'' had.
''System Shock 2'' only sold about 58,000 units eight months after release, in contrast to ''System Shock'' 170,000 units.
As a result of poor sales of ''System Shock 2'' and ''Thief'' from its multimillion dollar budgets, Looking Glass suffered mounting debts and closed down in May 2000.
Irrational Games still wanted to make ''System Shock 3'', but
Electronic Arts
Electronic Arts Inc. (EA) is an American video game company headquartered in Redwood City, California. Founded in May 1982 by former Apple Inc., Apple employee Trip Hawkins, the company was a pioneer of the early home computer game industry ...
, which held the publishing rights to the franchise, felt sales of the second were not sufficient to justify a sequel, leading Irrational to make a
spiritual successor
A spiritual successor (sometimes called a spiritual sequel) is a product or fictional work that is similar to, or directly inspired by, another previous product or work, but (unlike a traditional prequel or sequel) does not explicitly continue th ...
that shared the same concepts but avoided the intellectual property rights issues in ''BioShock''.
Jody Macgregor of ''
PC Gamer
''PC Gamer'' is a magazine and website founded in the United Kingdom in 1993 devoted to PC gaming and published monthly by Future plc. The magazine has several regional editions, with the UK and US editions becoming the best selling PC games m ...
'' noted that there are other factors contributing towards lower sales - including other competing games and changes in a sequel's marketing and approach. He also states that immersive sims require more commitment from the player to invest and learn the game's complex interacting systems in contrast to other types of games built around simpler mechanics thus making immersive sims harder to sell. Jordan Thomas, a developer on ''Thief'' and the ''BioShock'' games also said in 2017 that immersive sims are very difficult to be built by groups other than large teams due to the complexity of such games - making contributions from
indie games unlikely.
''
Polygon
In geometry, a polygon () is a plane figure made up of line segments connected to form a closed polygonal chain.
The segments of a closed polygonal chain are called its '' edges'' or ''sides''. The points where two edges meet are the polygon ...
'' Cass Marshall identified that some indie developers were able to create successive immersive sims by single-person or small teams, including ''
Shadows of Doubt'', ''Corpus Edax'' and ''Ctrl Alt Ego''.
Arkane's
Harvey Smith believed that while the sales trends for immersive sims in the 2010s were disappointing, there will always be a market for them but there will be a need to balance the cost of development to lower sales numbers.
Smith attributes the lower sales of more recent games to the general trend of players favoring fast-paced action games with strong multiplayer components - with publishers being wary of games without such elements. Immersive sims by nature tend to be single-player experiences requiring thought-out approaches but Smith believes that the new titles will adapt to these player preferences in the future, particularly from indie developers.
Lineage

A small number of studios and developers have been associated with the immersive sim genre, creating a lineage in its development originating from
Looking Glass Studios and its projects. ''Ultima Underworld'' was created by
Paul Neurath and
Doug Church, under their studio
Blue Sky Productions and
published
Publishing is the activities of making information, literature, music, software, and other content, physical or digital, available to the public for sale or free of charge. Traditionally, the term publishing refers to the creation and distribu ...
by
Origin Systems.
Warren Spector of Origin (who had worked on ''
Ultima VI'') also worked closely with Blue Sky to finalize the game - which eventually transitioned into Looking Glass and created ''System Shock 2'' and ''Thief''.
Spector later joined
Ion Storm and founded its
Austin, Texas
Austin ( ) is the List of capitals in the United States, capital city of the U.S. state of Texas. It is the county seat and most populous city of Travis County, Texas, Travis County, with portions extending into Hays County, Texas, Hays and W ...
studio where they developed the ''Deus Ex'' series.
Looking Glass Studios eventually closed down but developers from it launched their own studios - notably
Ken Levine who had helped with ''Thief'' and ''System Shock 2'' left to form
Irrational Games and create the ''BioShock'' series (which has been described as a
spiritual sequel to the ''System Shock'' games). Following the release of ''
BioShock Infinite'', Levine significantly pared back Irrational Games to reform under a new name,
Ghost Story Games, as to explore a new approach towards storytelling. However,
Jason Schreier
Jason Schreier (born May 10, 1987) is an American journalist and author who primarily covers the video game industry. He worked as a news reporter for ''Kotaku'' from 2011 to 2020 and was recognized for several Investigative journalism, investig ...
observed that many of those that had worked on the ''BioShock'' series at Irrational or other related studios often ended up either at existing studios or created their own studios that made their own immersive sim take on ''BioShock'' and continued this lineage.
Separately,
Raphaël Colantonio had been part of the quality assurance team supporting Origin Systems for
Electronic Arts
Electronic Arts Inc. (EA) is an American video game company headquartered in Redwood City, California. Founded in May 1982 by former Apple Inc., Apple employee Trip Hawkins, the company was a pioneer of the early home computer game industry ...
(EA) in publishing games like ''System Shock'' in Europe. Colantonio left EA and eventually founded
Arkane Studios
Arkane Studios SASU is a French video game developer based in Lyon. It was founded in 1999, and released its first game, ''Arx Fatalis'', in 2002. The studio has created the popular Dishonored (series), ''Dishonored'' series as well as developi ...
, desiring to make an immersive sim sequel to the ''Ultima Underworld'' series. EA denied them the use of the intellectual property and instead Arkane produced ''Arx Fatalis''. Later, Colantonio brought on
Harvey Smith (a quality assurance tester for Origin for ''System Shock'' and one of the lead developers under Ion Storm for ''Deus Ex'') and they subsequently designed the ''Dishonored'' series as well as building the new ''Prey'' atop similar immersive sim fundamentals.
More recently, Neurath founded a new studio,
OtherSide Entertainment obtaining the rights for an ''Underworld'' sequel from EA and for the ''System Shock'' property through
Night Dive Studios whom also had acquired the rights from EA. Neurath brought on Spector to help create both sequels.
Many immersive sims that feature numeric passwords (such as ''
BioShock'', ''
Prey
Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not ki ...
'', and ''
Deathloop'') use 451 or 0451 as part of the first code that the player encounters.
This is in reference to ''System Shock'' games, which use it as part of the first door codes seen in the game; it is sometimes believed to be a reference to the
Ray Bradbury
Ray Douglas Bradbury ( ; August 22, 1920June 5, 2012) was an American author and screenwriter. One of the most celebrated 20th-century American writers, he worked in a variety of genres, including fantasy, science fiction, Horror fiction, horr ...
novel ''
Fahrenheit 451
''Fahrenheit 451'' is a 1953 Dystopian fiction, dystopian novel by American writer Ray Bradbury. It presents a future American society where books have been outlawed and "firemen" Book burning, burn any that are found. The novel follows in the ...
'', though Spector stated in 2019 that this was not the case and that the code was used simply because it was the security code for the door of Looking Glass' studios in Cambridge. However, former Looking Glass programmer Marc LeBlanc said in 2023 that the code had originally been a Bradbury reference and that the studio's door code was set in reference to the game. Since then, the number's recurrence in immersive sims and various other games (such as ''
Call of Duty: Modern Warfare'', ''
Firewatch
''Firewatch'' is an adventure game developed by Campo Santo (company), Campo Santo and published by the developer in partnership with Panic Inc., Panic. The game was released in February 2016 for Linux, OS X, PlayStation 4, Windows, and Xbox ...
'', and ''
The Last of Us Part II'') has been described former Looking Glass developer Tim Stellmach as "kind of a signature that developers use to align themselves with Looking Glass".
The name of Looking Glass is also played upon by developers of immersive sims to reflect on the importance of the seminal studio to the genre; for example, OtherSide Entertainment's name (playing on the title of Lewis Carroll's book ''
Through the Looking-Glass
''Through the Looking-Glass, and What Alice Found There'' is a novel published in December 1871 by Lewis Carroll, the pen name of Charles Lutwidge Dodgson, a mathematics lecturer at Christ Church, Oxford, Christ Church, University of Oxford. I ...
'')
and ''Prey'' having the Looking Glass computer system that the player encounters frequently.
References
{{Looking Glass Studios
Video game genres