What is an 'Immersive Simulation?'
You might have thought immersion was the entire point of simulation--but you would have been wrong.
My favorite genre of game, the so-called 'Immersive Simulation,' has been much discussed on this blog. But I've never taken the time to express what this vague descriptive actually means to me, as a critic, and as such have found it hardly any more useful as a term in my toolbox than the non-existent literal meaning of those two words together. It's time to rectify that fact.
Definition
An ImSim is a narrative-heavy, systems-driven, non-linear, RPG-ish first person shooter/stealth game. Most of these qualifiers are negotiable, but the unifying key is systems-driven. ImSims are about gameplay--they emphasize skill tree development, upgrades, gadgets, exploration, and the creation of a personally tailored toolset to overcome obstacles. In this sense it isn't a genre so much as it is a philosophy, and like any philosophy, elements of its theses can be taken from the whole and incorporated piecemeal elsewhere.
You might also know ImSims as games where there are audiologs to pick up while wandering around claustrophobic environments. Many years ago this might have been enough to get the point across, but like with most other kinds of games, ImSims have generically diffused throughout the medium. You'll find bits and pieces of their design philosophy sprinkled throughout the games industry as of 2023.
Examples
The ImSim exists on a spectrum. An ImSim is frequently, but not always, a cRPG. It's usually, but not always, first person. It generally, but not exclusively, features stealth systems. I view the genre as consisting of the following categories, broken down by franchise:
True Immersive Simulations
Prey
System Shock
The true ImSim is, in my opinion, an exclusive category. It consists only of Prey (2017) and System Shock 2 (1999). These games fill all criteria listed above, but additionally are true open worlds: you always have access to the entire map, at any given time--although the individual areas need to be unlocked. Both are narrative focused, with special effort taken to integrate systems and storytelling. Both feature stealth, audio logs, and unguided gameplay; both encourage experimentation and reward creativity; and both have significant focus on character development mechanics. Neither are quite roleplaying games, but they're very close.
Prey is the ultimate, pure, true expression of the ImSim, thanks to Raphael Colantonio's genius systems, Arkane's well-honed level design talents, and Chris Avellone's stupendous narrative design. There are no cutscenes and no QTEs: only systems, audiologs, and freedom.
Effective Immersive Simulations
Deus Ex
Dishonored
Blood West
Thief
The effective ImSim consists of these four franchises, and perhaps a few others. What separates them from the true immersive simulation is the lack of an overworld, with the maps instead being hub-based. It's an important distinction, especially with Thief and Dishonored, which are in fact mission-based games. But it's also a minor one.
What distinguishes these games into their own genre is their shared emphasis on non-linearity. ImSims do not have QTEs. They rarely have setpiece action. They generally place the player in an environment and tell him to go wild. Despite vast differences in setting and tone, they feel conspicuously similar to each other for this shared philosophy.
cRPG Immersive Simulations
Vampire: The Masquerade - Bloodlines
Arx Fatalis
Weird West
It can occasionally be challenging to draw the line between cRPG and ImSim. The obvious reason is that there is no clear line. Still, these three games above are what I would consider generally matching the qualifications to be considered Immersive Sims, but are decidedly slanted toward roleplaying game elements. Bloodlines has a heavy narrative focus, with an emphasis on dialogue trees, but is in style and feeling pure ImSim. Arx Fatalis is inscrutable due to being old and shit, but possesses the same general qualities as even the true ImSims. Weird West fails in its systems focus too much to be considered a real ImSim, but was clearly intended as a game more like Prey.
There is no contradiction. A cRPG--like Deus Ex-- can be an ImSim in philosophy.
Immersive Simulation-likes
BioShock
Dark Messiah of Might & Magic
Atomic Heart
Alien: Isolation
The Immersive Simulation like is a development that began with Dark Messiah and exploded with BioShock. These games are often referred to as ImSims, and may even be marketed as such (BioShock), but tend to be more linear, more action focused, and less systems-driven than the others listed above.
Oftentimes their similarities to real ImSims are superficial, as in BioShock. While BioShock does have character building, and it does have some minor systems-driven interactions, it's also a mostly-linear action game. Only a few sections of the first game are open to any meaningful extent. Most of its ImSim feel comes from the environment, the atmosphere, the themes of identity and agency, and the fact that there are audiologs everywhere. Infinite is closer to ImSim, but it's similarly too linear and action focused to be considered a true member of the genrr.
Dark Messiah of Might & Magic is systems-driven--brilliantly so. But while its levels are open, they're also linear. There are no hubs, and there's only one solution to navigation and environmental puzzles.
Atomic Heart's ImSim inspirations are less worn on its sleeve and more blared in the player's face with a spotlight. It succeeds as an ImSim in ludonarrative consonance and open-ended gameplay, which includes stealth, but fails in narrative and level linearity. There are way too many cutscenes, way too many QTEs and puzzles, and far too few interactions between guns, the environment, and abilities for it to truly qualify. You can read more about my thoughts on this question in my review.
Alien: Isolation is a strange exception. It fits every ImSim qualifier, important and superficial, with enough style to qualify as an additional True Immersive Simulation, as per my definition. But while it's a mostly systems-driven game, it lacks the openness of a real ImSim--not in its environment, which is a rival to Prey's, but in its gameplay. In Prey there are no Typhon who are conveniently invulnerable for no clear reason. But the alien in Isolation is arbitrarily immune to shotguns and revolvers, and objectives are never defined by the player: instead, you're told what to do and where to go, and most are accomplished in linear ways.
I made it down to the reactor core in Prey by carefully constructing a gymnasium of Gloo, which I could scale up and down in order to bypass patrolling Typhon. There was really no other way to do it, as I was playing on Nightmare difficulty, while also doing my No Needles powerless run. No designer ever contemplated a player being insane enough to spend an hour doing this--but the systems were robust enough to allow me to anyway.
Isolation has nothing analogous to this. For that reason I relegate it to the ImSim-like category.
Immersive Simulation-inspired
Fallout (3, 4, New Vegas)
Dead Space (2023)
Deathloop
Many more examples abound, but for brevity's sake I'll restrict myself.
I believe it's worth discussing the 3D Fallout games as semi-ImSims. Even at their worst, Bethesda's two FO titles are non-linear, somewhat systems-driven, generally character-malleable RPGs in which you can solve various problems with differing solutions ('differing' meaning genocide, usually). They're also first person shooters with heavy exploration emphasis. I wouldn't call them ImSims--that isn't their intention. But they have much in common thematically with the other games discussed here.
The same is true for New Vegas, maybe even truer, but in its case I think the design is shifted so far toward the sandbox cRPG that it no longer qualifies even as semi-ImSim inspired. New Vegas isn't an immersive sim; it's Fallout 2 in 3D.
Dead Space (2023), and to a lesser extent the original, is also taking cues from the proper immersive sims. There are audiologs everywhere, and the map is open. Exploration is important, care has been taken to creative ludonarrative consonance in the upgrade schemes, atmosphere is vital, and there are numerous sandbox-like systems--such as tearing limbs off necromorphs to use as weapons--that shift the balance of the gameplay toward the systems-driven. It loses points for being in third person, having a strong focus on a linear story, and generally lacking in solutions to problems that haven't been intended by any level designer.
As for Deathloop--I'm still not sure what to make of it. It seems to be trying for immersive simulation, but it doesn't do a very good job.
Conclusion
To call a game an 'immersive sim' is simply to say it excels in the gameplay version of Unconstraint. As New Vegas permits the player to take any path to advance the narrative, so too does Prey allow the player to use any tool to overcome any obstacle. Something blocking your path? You could go around, or buy a neuromod to lift it out of the way, or throw a recycler charge and call it done. You might not be able to overcome any problem with any tool--just as how you cannot literally take any path to the Battle of Hoover Dam in New Vegas--but you can overcome most problems with many tools.
And at its core, that's what an ImSim is to me. It's a game where you look at a problem and solve it however you see fit. Not in the way that has been set out for you by the designers, but in the way that your brain has decided makes the most sense. Be that stealth, magic, combat, or some strange gadget, or all combined, it always comes back to you in the end. This makes them the precise opposite of puzzle games, and explains why I'll always love them so much.