Fackler Scale of FPS Realism

The extent to which an FPS is a simulation of real-world shooting and combat.

FPS on the classic end of the scale are characterized by fast movement, bunny-hopping, dominance of slow-projectile explosive weapons (rockets), large health gauges (or regenerating health) to allow for longer duels, nerfing of the accuracy/firepower of direct-fire automatic weapons for gameplay/fun purposes, and fun tricks like rocket jumping. Vehicles will be easy to pilot, able to dodge/strafe, and able to shoot reasonably well while moving. Hyperspace Arsenals are common. Items are placed on the ground very unnaturally or are even spinning in the air. Near the classic end of the scale, Artificial Stupidity is common for balance purposes. Bosses will be larger-than-life and over-the-top.

FPS on the realistic end of the scale are characterized by slower/fatigue-restricted movement, use of crouching/prone positions to increase accuracy and reduce visibility, dominance of sniper rifles and assault rifles, the need to use scopes or iron sights for long-range shots, recoil having a detrimental effect on accuracy (and discouraging the use of automatic fire), limited health (though the existence of the Instant Death Bullet is itself a sign of unrealism), and bleeding, leading to very short combat and an emphasis on the use of cover. Vehicles will require multiple crew to operate effectively and will be restricted by terrain. Usually no bosses, but if there are these usually are either as easy to take down with a Boom Headshot as yourself or vehicles that the bog-standard bullet hose can't scratch, forcing the need for anti-vehicle weapons.

At the far realistic end of the spectrum are the simulations. Rainbow Six debuted in 1998 and rewarded real-world tactics and tactical planning as a counter-terrorist unit. SWAT3 was similar, but introduced the need for non-lethal methods. Ghost Recon and Operation Flashpoint then attempted to simulate entire battlefields from the soldier's perspective.

Some of the elements like Regenerating Health are the most common in games in the middle of this scale.

The scale, of course, is not intended to be a judgment of gameplay. Being more realistic or unrealistic does not, in itself, make a game more or less fun, although different players have their preferences. It may be noted, however, that the popular market seems to have moved toward the realistic end of the scale since the online popularity and commercial success of Counter-Strike, leading to the commercial success of the Call of Duty/Modern Warfare and Battlefield series. The incorporation of realistic elements into mainstream FPS games seems more popular than ever. That said, both the Call of Duty and Battlefield series still favour arcade-style gameplay over realism.

However, with the mainstream adopting realistic elements, a niche was left for the old-school run and gun that Doom and Duke Nukem were all about. Serious Sam and Painkiller took the old formula and amplified it, with outrageously powerful weapons matched against legions and legions of monsters, with gore to match. The success of Team Fortress 2, with its cartoonish graphics on top of gameplay very similar to its Quake-mod forebear, is also good reason to expect that the classic FPS style isn't going away any time soon.

See also Mohs Scale of Science Fiction Hardness. Compare Acceptable Breaks From Reality. The way that the Standard FPS Guns are implemented generally varies on where a game falls on the scale, with cosmetically similar weapons having wildly divergent gameplay characteristics.

List is ranked from classic/unrealistic to realistic/simulation. Commentary on examples is encouraged. List is named for Martin Fackler, a battlefield surgeon who developed ballistic gelatin, used for testing the deadliness of firearms.

''Please note: This list of examples is ranked. That means classic stuff goes on top, and realistic stuff goes on the bottom. More classic items are closer to the top, while more realistic items are further away towards the bottom. So, if you know about a really, really realistic shooter, don't place it under "Realistic"; instead, place it at the very bottom of the list, right above "Realistic".''

Classic

 * Jumping Flash! -- It features a rabbit as the protagonist who must collect Muu Muus and can triple jump, so its place this far up the list is to be expected.
 * Serious Sam I and II -- Practically no reloading, thousands of incoming monsters with a simple AI and very few enemies with hitscan weapons, Hyperspace Arsenal with gatling lasers, very limited falling damage, cannibalism, Time Travel, and ass-whupping.
 * One of the most popular mods in the series called Parse Error / Serious Insamnity shifts the game further to classic style to the extreme degree. The player moves at the speed of a car, the amount of enemies is tenfolded and weapons are incredibly overpowered to match the amount of enemies. In addition in Serious Sam II variation, most of the weapons are akimbos, including cannon.
 * Painkiller -- Rather similar to Serious Sam in terms of More Dakka, over-the-top weapon design with no reloading, level layout, and monsters with a simple AI.
 * Metroid Prime -- Samus Aran is a Powered Armor-wearing walking tank with an impressive vertical leap and an assortment of high-powered energy weapons, facing a series of large, monstrous, alien creatures. Although the emphasis is as much as if not more on exploration than combat.
 * Warsow, Gameplay similar to the first 3 Quake games but the game actively encourages bunnyhopping, walljumping and other trick maneuvers. Players move at insane speeds and player can carry many weapons at a time (although the ammo is rather limited compared to some other arena-style shooters) and there is no need to reload them.
 * Hard Reset -- No reloading, semi-infinite ammo, no regenerating health (bullet time included when badly injured), regenerating shields... not a lot of jumping, but a lot of hard, explosive, fast-paced Doom-style run and gun action with Serious Sam-style giganto-bosses and weapons that are (mostly) realistic in terms of concept but versatile and definitely not realistic in execution. In the words of Rock Paper Shotgun, it's "a shooter that remembers shooters were meant to kill you".
 * Doom I and II, Wolfenstein 3D - Pre-dating Serious Sam and Quake (obviously). No aiming, no reloading, hyperspace arsenal, basic level design, no falling damage, lots of monsters to blast. The respective sequels are further down, but not by that much.
 * Serious Sam 3 -- Slightly more down the scale compared to its predecessors with sprinting (although infinite), some weapons requiring to reload with two of them having iron sights. Not by much down the scale due to sheer number of enemies and retaining other gameplay elements.
 * Quake, Quake II and Quake III Arena -- Main character can jump like a grasshopper, or like a flea with explosives. Again, as with Doom I and II, ability to carry a lot of weapons and ammo, no reloading, basic level design, but there are fewer enemies with more complex AI.
 * Alien Arena, as a combination of Quake and Unreal, players move at rather fast speeds, player can carry all the weapons with lots of ammo, there is no regenerating health or weapon reloading.
 * Unreal -- Ditto. No reloading except for the automag pistol and still focusing on an arcade-like blasting experience. The amount of enemies in the original is fairly low with some having fairly complex AI. However, the game usually encourages to fight in the open. From Unreal Tournament 2003 onwards, double jumps and wall jumps (sometimes combined) were also added, and mutators can be tossed in to make the game even more arcadey.
 * Turok -- Ditto, although the 2008 Continuity Reboot game is closer to the realistic end, just a little past Doom 3 and Quake IV. However, Turok II: Seeds of Evil features one of the most impressive Hyperspace Arsenals and no falling damage.
 * Dark Forces Saga -- The first game was quite Doom-like (although with a more coherent plot and mission objectives). Jedi Knight and especially Jedi Outcast are initially much more towards the realistic side, but all that goes out the window once you get your hands on a lightsaber and force powers.
 * Gunz: The Duel -- Very difficult to hit things once you hit high levels, due to Game Breakers and "Stop Having Fun!" Guys encouraging more Quake-inspired gameplay.
 * Blood -- A lot like the below Duke Nukem, set a decade after World War 1. Ranks slightly higher, due to supernatural influences on literally everything in the game.
 * Duke Nukem -- Tougher, smarter, more maneuverable monsters than Doom (for the time, of course), and more complex levels. You gotta reload your starting pistol, but you're still trotting around with dual rocket launcher gloves and a shrinking ray. Duke Nukem Forever is slightly higher on this list, being more Halo-like.
 * Time Splitters -- aim wobble, no jumping, no health restore during storymode but... as many weapons as you can carry, Dual Wield assault rifles, man portable miniguns, the ability to stick all mines to other players, and split second reload. Though, health and armor restoration and reload glitching was fixed in the third entry.
 * Team Fortress Classic: Starting with the realistic elements, what few there are: Teamwork heavily encouraged, Short Range Shotgun is averted (in fact, most guns have pretty realistic spread), grenades, you could only care around four weapons and eight grenades per class, and you have to reload your shotguns, grenade launchers, and rocket launchers (which also technically averts One Bullet Clips, since these weapons are reloaded one round at a time). Now for the unrealistic elements: Frantic, fast, arcade Quake style gameplay, Bottomless Magazines on plenty of weapons (and strange reloads for the others), Grenade Spam, unrealistically high running speeds, even the most fragile classes can take an unrealistic amount of damage before dying, Rocket Jump, Charged Attack sniper rifles, a Medic who can instantly heal you by hitting you with a medkit, and several "futuristic" weapons like rail pistols and EMP grenades.
 * Team Fortress 2 -- Revels in its over-the-top ridiculousness, just like its predecessor. Once again, realistic elements first: You can only carry three weapons at once (a primary, a sidearm, and a melee weapon), you have to reload most of your sidearms and some primary weapons (like the pistol, grenade launcher, shotgun, rocket launcher, and double barreled shotgun called the Force-A-Nature), the physics engine causes the grenade launchers projectiles to bounce realistically, and cause most guns have reasonable ranges (the shotgun and pistol both are capable medium range weapons), and teamwork is much more encouraged than its predecessor. As for the unrealistic elements: Critical Existence Failure, Made of Iron characters, the cartoonish art style, Bottomless Magazines for a few weapons like the flamethrower and minigun, man portable miniguns, Rocket Jump, sodas that if drunk make you temporarily invincible, and much, much more.
 * Note that cartoony graphics isn't the only thing unrealistic about the visuals, looking at the melee weapons we have a postal box, trophy, and a golf club as just a few of the silly weapons. Also note the fact that their is a shield made out of wood which increases fire resistance. Think about that for a second.
 * If it does damage, you can kill somebody with it. That includes a roll of wrapping paper, your bare fists, an icicle, a dead fish...
 * Borderlands -- Hyperspace Arsenal and teleportation systems that run on Handwavium, low emphasis on cover, and bullets that shoot lightning, acid, fire, and explode, shotguns that shoot rockets in six-round bursts, absurdly effective revolvers that shoot shotgun shells. Rather like TF2 it revels in the ridiculous, and makes no attempt to justify it.
 * Marathon series -- Too primitive for vehicles, good AI, or working cover, but makes an effort with the technology it has. One Bullet Clips are notably averted, and Made of Iron is handwaved with a shield mechanic. No hit-scans, i.e. bullets do not hit instantaneously, but they have a set speed. No falling damage, although this is handwaved as the player being a cyborg. The player's weapon must be aimed up or down to hit things above or below them.
 * An honorable mention: the additional sniper rifle weapon added to the "A Week in Paradise" mod to Postal 2, which featured a need for the player to lead a moving target. Ballistic features for the sniper rifle alone seen in few, if any, other shooters... and for an game that actually has default controls for urinating (the better to douse flames with), or for yelling "get the fuck down!" Quite a feat.
 * GoldenEye -- Player can carry as many weapons as he can find, some of which have infinite ammo. Player can at one point dual-wield a machine gun and a grenade launcher. Player can also drive and fire a Russian tank single-handedly (though this is handwaved in Nintendo Power by mentioning that Bond spent a week at Heavy Armor Training Camp) and using it as a cheat in other levels makes it mansized. However, there is no way to restore health. Putting on suits of body armor will absorb damage until it deteriorates, but that's it.
 * Perfect Dark -- Marginally more realistic than Golden Eye 1997. Hyperspace Arsenal and One Bullet Clips still exist, but reloading is now animated and much slower. Additionally, there is an Energy Shield instead of armor and the ability to crouch with scoped guns for greater accuracy.
 * Doom 3, Quake IV, Return to Castle Wolfenstein -- An emphasis on smaller levels with enemies that are fewer in number but tougher and more intelligent. Additionally, the player characters move slower and can take less damage than their classic counterparts and a lot of weapons need to be reloaded. Still, you have a Hyperspace Arsenal and shootouts are still largely run-and-gun, although some use of cover is encouraged.
 * Bio Shock -- A Hyperspace Arsenal, an abundance of healing options, Doom 3-like run-and-gun gunplay, relatively low emphasis on cover, and an assortment of spell-like Plasmid superpowers. On the other hand, the early-mid 20th century era weaponry is somewhat restrained (i.e. the revolver and shotgun have very limited ammo capacity, while the tommy gun is quite inaccurate at range), character movement is relatively slow, and the game does encourage tactical use of your Plasmid powers in combination with your weapons to overcome the more challenging obstacles (the Big Daddies in particular).
 * Starsiege:Tribes & Tribes 2 -- You can carry only a limited number of weapons (depending on your armor size), grenades, and a single backpack. Teamwork is needed for effective attacks against the enemy base. However, you have jetpacks, plasma cannons, and mortars which fire miniature nukes shaped like fat footballs, you can repair your damage with a infinite-use Repair backpack, and you can shield almost all incoming damage with shield backpacks. In addition, even the slowest classes move at high speeds and the fastest classes can leave even a lot of cars behind so there's even a speedometer in some installments.
 * Half Life -- Enemy squad tactics ranging from hurling grenades to flush you out to sending in troops one at a time to see if you're dead, taking cover, and such. Taking cover was also encouraged when fighting human enemies and there are no Bottomless Magazines on real world guns. On the other hand, your armor can take several dozen bullets, you can carry a small arsenal of weapons and ammo, you can run at 40 miles per hour while wearing a metal suit and carrying 15 weapons, some guns have unrealistically large magazine sizes (the submachine gun can hold 50 rounds), the grenade launcher under the submachine gun never needs to be reloaded, and most of the cleverer things your enemies do are faked with scripting.
 * A spinoff of the famous SMOD of the sequel ranks harder on the scale, though still using a Call of Duty-style healing system, or the game's regular med-kits. Newer versions are to include a "bandage" system that forces players to stop and heal.
 * The sequel, Half Life 2, was moderately more realistic. There is a very realistic physics engine, guns are slightly more accurate across the board, your enemies will do those intelligent things even without scripting, magazines are smaller forcing you to reload more often, cover is more encouraged, there are a few vehicles you can drive, you don't run nearly as fast, and many enemies are more fragile (those who aren't are handwaved as being cyborgs). One Bullet Clips, Critical Existence Failure, Made of Iron characters, your Hyperspace Arsenal, and unrealistically short weapon ranges (rather similar to Halo or Fallout) are still there, however.
 * Halo --- You can only carry two weapons, vehicles abound, cover encouraged, et cetera. On the other hand, you had a regenerating energy shield that could take varying amounts of damage according to difficulty. First game had a health bar, while the second and third removed it entirely. Also, moving has no effect on accuracy, and shootouts are often much more "run-and-gun" than "peek-and-lean", although the regenerating health mechanic does encourage hiding behind cover when injured. The forth game has moved back towards realism, with health and lowered accuracy from motion.
 * Fallout 3 -- Player inventory has a weight limit, though it is generous enough to allow the player to carry dozens of guns (handwaved via the existence of power armor). Gimmicky weapons exist (gatling lasers, portable nuke launchers, etc.), but focus is very much on standard firearms. Weapons degrade and jam, but can be repaired by scavenging parts from similar weapons. Damage model distinguishes individual body parts, with appropriate effects depending on the part that is affected, though it still takes a lot of firepower to kill the player and it is possible to spam medkits in combat. Player can use awareness-increasing drugs, which help in combat, but they typically have withdrawal effects. Most guns have rather unrealistically wide bullet spread, requiring for most weaponry to be used at closer ranges then would be realistic to not waste ammunition.
 * The sequel Fallout New Vegas is more of the same, but it includes an optional "Hardcore" mode that shifts the game further towards realism: ammo has weight, healing takes time, and fatigue, hunger and hydration are tracked.
 * New Vegas is arguably much more realistic in terms of gunplay, including ironsights, weapon mods, much more limited bullet spread, etc.
 * Killing Floor -- No crosshair. Players have a weight limit on their inventory, and bigger weapons slow movement speed when they're held. They also take heavy damage from specimens if they haven't bought armor. On the other hand, friendly fire is off by default, One Bullet Clips abound, and the enemies are mutant clones that can survive having their heads blown off and that you get random bullet time from.
 * Crysis -- The same as Far Cry (see below), but with a "nano-suit" to explain the inhuman strength. Also, has quickly regenerating health and an assortment of nanosuit-based superpowers.
 * Far Cry -- Player can only carry a limited amount of weapons, but this includes machine guns and rocket launchers. Heavier weapons do, however, slow movement. Movement is relatively slow, and movement significantly reduces firing accuracy, encouraging you to fire while crouching or leaning behind cover. Additionally, health and armor pickups are relatively uncommon, and on higher difficulty settings you can only survive a few shots. Combat against human enemies is fairly realistic, with stealth often coming into play, but when you face off against mutants the gameplay becomes much more like a classic shooter.
 * F.E.A.R. -- Similar to Far Cry, but with incredibly advanced enemy AI. The one catch is your paranormally-induced bullet-time reflexes. Without those, the enemies would probably kill you every time. You also know Kung Fu.
 * No One Lives Forever -- Similar to F.E.A.R. (the enemies even use some of the same animations), only with more primitive A.I., no bullet-time superpowers (or Kung Fu), and much more emphasis on stealth.
 * Gears of War -- Uses regenerating health, but includes a cover system that popularized the concept. Characters are also capable of rolling around as much as they want, potentially lengthening firefights, but averts Critical Existence Failure by putting characters into a weakened mode after taking enough damage (if not outright killed). However, characters can take a fair amount of damage before that happens, automatic weaponry usually taking around 3-5 seconds to cause that.
 * Battlefield 2142 -- Although it's rather realistic for the most part, the vehicles are Humongous Mechas.
 * Left 4 Dead -- Two weapons only, and one of them is always a pistol or (in the sequel) a melee weapon. Weapons can shoot through walls slightly and can penetrate multiple targets. Has friendly fire on Normal and above, and getting a shotgun blast from a fellow Survivor is an insta-teamkill on Expert. Using medkits for a permanent heal takes a while, during which time the user cannot shoot, while pills offer only a temporary boost that slowly runs down. Survivors fire, move and reload slower the more injured they are. An update also made it impossible to continuously melee. The mounted minigun has a windup time, can overheat and can only cover a limited field of fire. The shotguns reload one shell at a time. No rocket launchers, and grenade launchers only appear in the sequel (and are very rare). On the other hand, pistols serve as an unlimited-ammo Emergency Weapon, and they can be dual-wielded without loss in accuracy. The minigun has unlimited ammunition too. There are stocks of infinitely-usable ammo around. The hunting rifle can be used well without needing the scope. The other guns also use One Bullet Clips. Oh, and there are zombies with numbers of hundreds per level and sometimes even over a thousand.
 * Combat Arms -- Really up and down about this. Health does not regenerate, and a small amount of bullets are generally necessary to kill someone, causing people who stand still to in a lot of trouble. However, running around and out-shooting your enemies usually works. One Bullet Clips are in full effect, though Hyperspace Arsenal is effectively averted by only allowing a main weapon, a sidearm, a melee weapon and extra two extra things for your backpack at most -- you aren't even allowed to get more ammo for any gun, all weapons picked up has the exact same ammo as it did when its holder was killed. Armour in the game also is mostly nullified by melee attacks and explosions, aside from one exception -- usually like in Real Life. Headshots kill in one hit unless you are wearing a helmet, which only gives you a chance of not being killed in one hit. Moving hurts your accuracy, there is recoil which is exceptionally noticeable with automatic fire, and using a scope is necessary for farther shots -- but you are unable to utilize your gun's iron sights if you lack a scope. In execution, the game is generally more run-and-gun on smaller maps with respawning available, and more tactical without said respawning or larger maps.
 * Total Overdose uses realistic features only in as far as it supports more dramatic gunfights, then throws in Bullet Time Gun Fu and completely unrealistic special attacks that exploit Rule of Funny and Rule of Cool.
 * Action Quake, The Specialists, Action Half-Life, Action Unreal Tournament mods for those respective games, and now The Opera, use realism much the same way as various action film genres, just enough for dramatic battle.
 * Deus Ex -- Player has a limited amount of space to carry all items, including weapons (which are the bulkiest items by far -- the inventory system is a forerunner to the briefcase in Resident Evil 4). Weapons are fairly inaccurate unless the player stands still, crouches, or spends points on weapons training. Player must pick up weapons and ammo deliberately by looking at them and clicking, as opposed to simply running over weapons or ammo. All characters take separate damage to individual parts of the body -- taking excessive leg damage will slow you to a crawl, taking excessive arm damage will mess up your aim, and taking excessive chest or head damage is fatal. However, health is easily restored by medkits or medical bots, including broken limbs. Also, once you develop your nano-augmented powers sufficiently, you can run as fast as a speeding car and regenerating bullet wounds almost instantly.
 * Far Cry 2 -- Player can carry only four weapons at a time (of those, two are a knife and a pistol, leaving only enough room for 2 rifle-sized weapons). Player must aim with iron sights as there is no on-screen crosshair. Player must use cover effectively to survive. Player must stop and heal serious wounds to avoid bleeding to death. Player has freaking malaria. On the other hand, syringes (and bottled water) somehow restore health even though most of the damage you take is from bullets.
 * Even with the inventory limit, realism is still iffy. One can conceivably cart around an M79 with 5 grenades, a SAW with 500 rounds, and a sniper rifle with 50 rounds. Plus 5 hand grenades and 5 molotov cocktails. Also, this is the game where almost any damage to a vehicle (Collision, fall off a cliff, riddled with bullets, set on fire) can be repaired by opening the hood and tightening the radiator cap.
 * Call of Duty/Modern Warfare -- Cover emphasized. Shooting is inaccurate unless you use iron-sights -- though when you do use them, accuracy is practically what you'd expect of lasers, allowing you to kill snipers that are less skilled. Shotguns are very short-ranged. However, uses a health system that, depending on your difficulty, takes anywhere from a full magazine to one or two bullets to deplete your health, but regeneration makes you fine and dandy shortly afterward.
 * Call of Duty is all over the scale due to its multiple game modes. While Hardcore multiplayer matches and singleplayer on harder difficulties can be pretty realistic (you can die by taking just 2-3 hits), standard multiplayer can get VERY ridiculous for Rule of Fun. The Perks system is what really makes things unrealistic, as it can let players reload faster than should be humanly possible, sprint indefinitely, and take no damage from falling. Also interesting to note is that, in all game modes, Concealment Equals Cover is averted, thanks to wide-open maps (or, in small maps, very little cover even in rooms - and what cover there is can easily be rushed or penetrated with the right perk or attachment).
 * Vanilla mode only requires 3 bullets to kill a person with 100 health (hardcore gives people something in the region of 45), providing you're within range of damage drop-off of the weapon and you're hitting the chest or head (which apply a 1.1x or 1.5x damage modifier, respectively). Seeing as most rifles do 40-30 or 30-20 damage before the use of perks like "Stopping Power", which also adds a 1.4x modifier. It doesn't take a lot to kill somebody. Unfortunately, poor hit detection and netcode in Co D games, combined with the average person's inability to aim properly leads to a significantly higher amount of bullets used to kill a person. Something that is more apparent in Black Ops for numerous reasons.
 * Also, health is not the only factor involved in realism. Even hardcore mode on Co D still feels like an arcade game because you still move like someone in an arcade game. Lower health is only a small factor for realism.
 * Killzone is basically Call of Duty IN SPACE. The second game uses a cover system, and thus it is more emphasized than in Call of Duty - and it's quite necessary for survival. The first game was around Halo's level.
 * Likewise, Resistance is basically Call of Duty WITH ALIEN MUTANTS.
 * Medal of Honor -- Like Call of Duty, only (in the first several games) without regenerating health. You could still take a couple dozen SMG hits before dying, although healing items are somewhat common and enemies with automatic weapons and good aim can cut you down pretty quickly on harder difficulties.
 * Soldier of Fortune: Realistic enemy body damage (especially the second game, although damage doesn't slow you down), inaccurate aim when moving or firing automatic weapons, no regenerating health(except Payback), explosions are instantly fatal, some enemies have armor-piercing bullets and can One-Hit Kill you.
 * Battlefield series -- Fragile humans, war vehicles, squad combat, and the like. However, rockets don't kill humans as easily as bullets, among other things in the name of balancing out multiplayer. The ongoing mod Project: Reality is much more realistic on the scale, and Battlefield: Bad Company and Battlefield: Heroes is farther up.
 * Humans aren't that fragile, even in BF2. Similar to CoD, most weapons have a power in the region of 40-25, which still requires at least 4 or so bullets to kill someone. As with CoD, networking issues usually affects this and increase the number of bullets used by an individual by quite a bit. The only damage modifier in vanilla BF2 is for the head, which allows sniper rifles to only give one-hit-kills on headshots. Explosives don't kill people as easily because the splash damage of handheld explosives is reduced, as said, for the sake of balance. However they are perfectly capable of one-hit-kills, providing the target is hit directly.
 * Bad Company 2, at least, throws the whole explosives thing right out the window, with the Carl Gustav rocket launcher being one of the most effective anti-personnel weapons in the game, even moreso if you take the improved explosives perk. Not only is its splash damage sufficient to get kills off indirect hits, but it blows cover to pieces and is fast and accurate. Then there's grenade launchers, which many players believe to be the only truly overpowered weapon in the game. C4 can also be used very effectively if you know what you're doing. Hand grenades are also pretty strong, but you usually can only carry one.
 * Counter-Strike -- Mostly-realistic damage system (though you can move fine after being blasted in the leg), inaccuracy increases if you don't stop and aim. Also, no healing.
 * Global Operations is slightly lower on the scale, adding ironsights and tweaking movement, but the developers have gone on record to say they still want to keep it Counter-Strike and not some other game.
 * Alliance of Valiant Arms -- A game developed by a Korean company named Red Duck, it is essentially Counter-Strike with improvements such as better graphics (via Unreal Engine), 3 classes, passive skills (only helps a little), and 7+ modes. Recoil now shakes the screen up and down and you can now control the recoil better. Aiming down sights is useless on most assault rifles, with 3-4 exceptions(AK 107, AK 200, MG 4 KE, etc.), because of the mysteriously slowed rate of fire and increased recoil. The Korean version recently released many overpowered guns that operate like those from Call of Duty, making realism semi-dependent on the weapon you are using.
 * As of now, the M1 Garand has been released on the Korean version. For the first time, iron sights are available on a weapon. So logically, if everyone uses M1 Garand, then it'd be further down the list in terms of realism. On the other hand, if everyone uses the SA-58 Para or any other hipfire-only gun, then it'd be further up. As a result, most matches tend to be a hodgepodge of both Counter-Strike and Call of Duty: two completely different gameplay mechanics rolled into one. On top of that, some new guns have the options to select firing modes in-game while others' firing modes have to be selected in the inventory by adding/removing mods. Which gun has what feature depends entirely on its release date. With other WWII guns incorporated in the game since its release including PPSh and STG44, it's truly a monstrous conglomerate that has confused and is still confusing new players and veterans alike with each update.
 * Iron Storm -- The game isn't a true tactical shooter per se, but still requires you to take precise aim, choose your gear wisely and carefully fight your way through enemy territory. Do Not Run With a Gun is paramount not only for achieving victory, but for basic survival as well, in each of the six campaign missions. Sighted Guns Are Low Tech is carefully semi-averted (you can see them on every weapon, but can't really use them in-game and have to rely on traditional FPS reticules or a scope).
 * Mirrors Edge (has FPS elements in it) -- You'll jump and gain momentum pretty realistically and can carry only one weapon at a time (with limited ammunition), which usually have to be discarded to proceed through various obstacles. However, it does have regenerating health.
 * Brothers in Arms -- Places a strong emphasis not only on taking cover, but also on real infantry tactics like suppression fire and flanking maneuvers (which are pretty much essential to win, and the AI uses them as well). Also, weapons are extremely inaccurate without using the iron-sights (and pretty inaccurate with them too). No regeneration or healing, although you can still take a few bullets without dying or feeling any impact on gameplay.
 * Brothers In Arms: Hell's Highway had a unique health system that functioned much like Call of Duty's, except instead of taking hits, it was more like luck. The longer you leaned out of cover or were exposed while getting shot at, the more your screen turns red. Eventually, a single bullet finds its mark and you die/are severely wounded and have to go back to the last checkpoint. It's a system that encourages you to hug cover and not conserve ammo: on the higher difficulties, you won't have a chance to aim much, so snap shots are your friend. Much like they are in real life firefights at close range.
 * Mafia: The City of Lost Heaven has guns that are very in-accurate when fired standing and when moving. Only allows you to holster one larger weapon. One Bullet Clips and the Short Range Shotgun are averted, and pistols are very accurate and powerful. Health kits exist, but are very uncommon (only a few levels have one) and only regenerate 30 points. Enemies and player are fairly close in health. Reloading permanently discards partially used magazines (only the pump-action shotgun averts this which is reloaded one shell at a time).
 * STALKER: Shadow of Chernobyl -- Realistic "tactical shooter"-style combat, with lots of firing while crouched and leaning around corners. Notably, bullets are affected by gravity and can also richochet off surfaces. Healing items are in limited supply, but are insta-heal. You can only carry a very limited amount of stuff (50 kgs), and can only equip 2 firearms at a time (a pistol/small submachine gun and a larger weapon). Unless you're wearing military-grade combat armor, expect to die after only a few shots from an assault rifle. Each individual enemy is also just as tough as the player character, so a Mook wearing combat armor can soak more than half a mag of assault rifle fire before going down. However, weight doesn't affect movement until you go over the limit, and medkits heal instantly. (The game would be a LOT harder [hard as it already is] if it wasn't.)
 * The Source Mod Insurgency: Modern Combat. It features fully realistic firearms, as in all the firearms have a maximum range of several hundred meters. The main limiting factor is whether the player can even see the enemy, which is hard a lot of the time due to the long ranges (outdoors) and extremes of light (indoors), as well as all the smoke and sand everywhere. You can't see your ammo or health, and you have two methods of aiming: looking down the sights (which you will doing most of the time), and firing from the hip, where your guy freely waves the gun around rather than holding it in one position. Special weapons such as shotguns (which are effective at much longer distances than in most games), grenade launchers, smoke grenades, laser sights, and M4 assault rifles are only given to certain classes. Cover is very important, staying in the open will invariably get you shot. The best tactic is suppressive fire most of the time, and occasionally using grenades for flushing out enemies. Damage varies depending on range. The fully armored US soldiers can take only a few shots before dying. When shot, you'll flinch and the screen will temporarily turn red, and even near misses blur the screen to simulate suppression.
 * Call of Cthulhu Dark Corners of the Earth is surprisingly realistic for a game about fishmen breeding with humans and sea gods. Humans are fairly fragile, and the ones that aren't are handwaved as being half human hybrids. A few bullets will take out any enemy, and the player character and the enemies weren't that far away in health. If anything, they had more health than the player usually. It's also got one of the most realistic body damage systems in video games. When hit, different things happen depending on what body part was hit. Getting shot in the leg causes you to move slower and drag your leg (complete with sound effects), and getting shot in the chests causes your gun to wobble around and your vision to blur, making it impossible to aim. The only way to heal your wounds is to apply bandages, sultures, and splints, (different medical supplies are needed for different wounds) which you must apply in real time, making doing this in the middle of a firefight next to impossible. However, you must do it really fast, because if you leave major wounds untreated, you'll actually bleed to death, where as minor wounds will heal by themselves. Also, there was no Hud at all. Meaning there was no health bar, no ammo indicator, and no crosshair. The only way to tell if you are dying is how much blood was on your screen, how grey your screen was, and how hard you were breathing in game. To keep count of your ammo, you have to mentally keep track of how many bullets you fired, and to aim, you have to aim down the actual iron sights on the guns. The only real unrealistic parts were One Bullet Clips, the ability to carry every weapon in the game simultaneously, the fact that applying a bandage will make any wound good as new, and that there are 7 foot tall alien fish men who would claw you to death unless you shoot them and giant sea gods you have to fight. On top of that, unlike a vast majority of FPS games, a weapon would not automatically plant a bullet at the center of the screen. Rather, it would depend on where the weapon's barrel was actually pointing, meaning that weapon sway is not merely for show. This not only applies for you, but for any mook with a gun as well.
 * Ghost Recon -- Original games had you die in one or two shots, and squad tactics were emphasized, the same as Rainbow Six. The later "Advanced Warfighter" games rank lower, but are still Nintendo Hard (at least, the PC versions are - the consoles are much like their newer counterparts) and also have the option of playing on the original difficulty -- that is, die in one shot.
 * Americas Army -- Being injured, walking, or holding your gun at the shoulder (rather than aiming by the scope) drastically decreases accuracy. The gun cannot be fired if the player sprints. Being shot twice in the foot puts a player near death, to say nothing of being shot in the torso or head. Health cannot be recovered, and blood loss can only be slowed by lying down, applying a one-time-only bandage, or being treated by a combat medic. Spare ammunition doesn't transfer from magazine to magazine, but each one instead holds exactly how many it holds. Shots can ricochet, but only rarely. Grenades and sniper rifles are king.
 * SWAT 4 -- Being a slower-paced and atmospheric tactical shooter, there is no jumping at all, you can either creep, walk at a standard pace or run very slowly. Crosshairs and the basic personal HUD are minimal. There is no healing for anyone. Single shots are often lethal, and even when they're not, being shot in the legs or arms will hurt speed or accuracy. The player can daze himself with his own flashbangs and stinger grenades. There are no frag grenades, explosive charges, rocket launchers, grenade launchers, light machine guns, anti-material rifles, or BFGs of any kind, with the most powerful weapon you can carry being the military grade M 4 A 1 Carbine, and all the grenades (tear gas, stinger, flashbang) being non-lethal, which fits given that SWAT is a paramilitary police unit, not part of the army. All weapons have a fully realistic portrayal of recoil and their respective drawbacks. In fact, the only thing not portrayed is bullet richochet. It's possible to customize one's bullet loadout (full metal jacket or jacketed hollow-point, etc.), and there's a focus on non-lethally neutralizing and apprehending criminals, rather that killing them outright. You're also punished for not following SWAT procedures, so if you shoot a perp without first ordering him to comply, points are docked for use of unauthorized deadly force. There are no saves at all, during any mission. The less-lethal flash bang and stinger grenade actually can injure or kill if detonated within close proximity to a person.
 * Red Orchestra -- A very harsh portrayal of WWII combat. There are no crosshairs and, when fired from the hip, weapons are not centered to the screen, but wander back and forth as you move. There are no crosshairs, no ammo counter, few HUD elements in general, and no healing at all. All weapons have significant recoil that must be carefully controlled when firing rapidly. Weapons can be rested against surfaces to steady them, and weapons with bipods (such as machine guns and anti-tank rifles) can be set up on any suitable surface. Ballistics are fairly realistically simulated with travel time and bullet drop, though no penetration or ricochets. Machineguns overheat if fired in long bursts, even to the point of warping and ruining the barrel. Damage modeling is severe and universal and one hit kills are common, especially if a person is shot in the head or torso. Wounds bleed, shrapnel takes arms and legs off, and direct hits from artillery shells can turn men into a red cloud. Combat is highly tactical, and which weapon you're given depends on your class. Since all classes except "Rifleman" are limited in number, most soldiers end up with a bolt-action rifle or, if they're lucky, a semi-automatic rifle or submachine gun. Cool Guns like sniper rifles and machineguns are limited in number and must be used wisely.
 * The game also approaches simulation level in its portrayal of tanks: Crew of One is averted, a tank must have at least a driver and a commander/gunner to be used efficiently. It's almost impossible for the gunner to aim the cannon while the tank is moving, so voice communication between gunner and driver is a must. There is no third person view, so the tank crew can only see through small view ports. To get a better view, they have to open the hatch and risk being shot in the process. Tank armor varies in thickness depending on the model and part of the vehicle, with rear armor being the weakest. Tanks can be disabled by penetrating the engine compartment or disabling the treads, or completely destroyed by aiming for the ammunition storage compartment. Shells that impact tank armor at a sharp angle will deflect off harmlessly.
 * World War II Online: Battleground Europe is a punishingly hard combined arms MMOFPS with a physics engine that includes full flight modeling, ballistics and vehicle damage models. The game is also heavily focused on teamwork and it is not uncommon to see operations pre-planned with marked artillery positions, infantry attack paths and other such stuff. The developers were even contracted in 2006 to produce a PC-based modern-day battlefield simulator for the British Ministry of Defence.
 * Rainbow Six -- The early entries forced you to make tactical decisions and aim carefully -- both you and the terrorists were easily killed, even if you were wearing heavy armor, which was useless against the common AK-47. You had to spend quite a bit of time planning which floors to breach and who to kill in the pre-planning stage, and you had to make it quick, since most missions had hostages in them. Later entries were less realistic, culminating in Vegas, which has a CoD-style healing system and arcade-y single player, with no pre-planning [except for gear loadout].
 * Also in the original, you were limited to one main weapon and one sidearm, plus a couple of magazines of ammo and a few grenades. That's for each one of up to sixteen or so soldiers however, and you could switch control between team leaders at will. Also notable is that the 'reload' function swaps your magazine for a spare one, averting One Bullet Clips.
 * The Operation Flashpoint series, the Arm A series and their professional derivatives Virtual Battlespace 1 and 2. The U.S. Army uses Americas Army for recruiting, but when teaching tactics using networked computers, they use VBS 1, a modified version of Operation Flashpoint (or more recently VBS 2, modified from Arm A). Yep, those games are that realistic.
 * Note that this mainly applies to the infantry/dismounted combat, and ARMA series vehicle operating is actually higher (towards Classic) on the realism scale for gameplay reasons, with 'games' such as the DCS series being even harder sim than ARMA in that respect.
 * Operation Flashpoint is crushingly realistic. Reloading with a partially used magazine puts that magazine back into your inventory for later use but you can't see which magazine is it until you load it. Wounds are severe, and you're just as mortal as your enemies. Being shot in the head or upper torso almost always means instant death, and being shot in the limbs can render you unable to walk or fire accurately. Combat usually takes place outdoors in wide open areas, and exchanges of fire often take place at ranges of 300 meters or more. Bullets take time to travel and drop over long distances, and even sound takes time to travel. Such is the detail of the game world that you can navigate by the stars at night, and the tides and sunrise/sunset times change depending on the time of year.
 * Even navigation can be a challenge in some missions. Some particularly sadistic mission creators will drop forty players into a dark forest without flashlights, compasses, GPS, NVGs, or maps. Only a few officers will have any navigational equipment at all, and everyone else has to make due by following the reflective cat's eyes on the back of the helmet in front of them. YMMV on whether this is crippingly realistic or freaking awesome.
 * The original game is set in 1985, so lack of personal GPS equipment or rarity of NV Gs is rather justified, especially in the case of USSR forces and partisans from Operation Flashpoint : Resistance.
 * There are some but very few unrealisms as well, mainly related to engine limitations, such as the awesome (and hilarious) sight of a tank driving onto a mine which explodes, sending the tank flying for a few meters until it lands on the next mine which finishes it off, and AI being ineffective indoors. Operation Flashpoint was originally infantry-only, and it shows.
 * There are also AI limitations that can easily happen if you screw up custom pathways in mission editor, leading to the OpFor not noticing their buddy right in front of them dropping in broad daylight.
 * There are mods to make the games even more realistic. Arm A II now has the fan-made ACE 2 advanced realism mod to go with it. Besides just outright adding more weapons, ammo, and gear to the game, a few examples of the features it provides would be an in-game simulation of a specialized wind metering device for snipers to fine tune their firing trajectories over large distances, and rocket launcher backblasts which emulate the potentially fatal injuries you would receive if you stood behind someone firing a Javelin missile in real life.
 * In large scale multiplayer gameplay with ACE mod, injuries trigger frantic attempts to get the wounded person to safety. Cue dragging the wounded, hefting the wounded over your shoulder and running, dropping equipment so you can carry the wounded without being slowed down, medics applying battlefield medicine with plasma, morphine, epinephrine, and bandages, and, of course, people running out of cover to try to help a wounded comrade and getting gunned down in the process.
 * According to the ACE wiki as of late January 2010, the mod has implemented nuclear weapons use in gameplay, complete with subsequent fallout whose location is affected by in-game wind. Fortunately this can be toggled, as can "markers" indicating the location and time (and hence how long you have until fallout appears) of any detonations. During mission creation'' vehicles may be granted NBC protection, which is effective in-game so long as the vehicle seals are not breached, i.e. by someone turning out or leaving the vehicle.
 * To take this Up to Eleven, there is a Project Reality mod for Arm A II. Considering how realistic Project Reality for Battlefield 2 is, even with the severe engine limitations...

Other

 * Whoever designed Real Life took it way out of hand. It's a popular opinion that IRL war isn't even fun.
 * Airsoft skirmishing can be considered all over the scale. Realistic-looking weapons (but with completely different ammo capacity and ballistics), more powerful weapons are often given minimum range restrictions to avoid injury (eg, a sniper being disallowed to fire on an opponent within 20 meters, and forced to switch to a sidearm - some fields force players to surrender to another if they're within ten feet, and so on), grenades and traps are different, cover and stealth encouraged, accuracy depends entirely on the shooter and their equipment, et cetera.
 * Play styles and site rules vary from casual skirmishing featuring lives, spawn areas, no restrictions on ammo capacity/rate of fire, and classic game types such as capture the flag and simple team based death matches. To mil-sim style play, incorporating real capacity magazines, team based camouflage and uniforms, and complex and variable objectives.
 * Certain manufacturers such as Systema produce premium brands of replica weaponry specifically for military and law enforcement training programmes. Featuring exact weights and dimensions (loaded & unloaded), correct fire rates, identical construction design regarding maintenance take down, replicated features such as burst fire modes and special safety options, and even ejecting shells. Conversely, a casual skirmish field can witness a sometimes chaotic and even bizarre mix of custom equipment, with certain pistols capable of out ranging lesser sniper rifles, large magazines carrying 5000+ rounds, modified guns firing at up to 3000+ rounds per minute (A real rifle avg ROF being in the range of 600 to 800), automatic desert eagles, grenade launchers mounted on pistols, pistols mounted on rifles, and cut down rifles mounted on rotary grenade launchers.
 * While paintball is somewhere in the "unrealistic" area, you may not survive more than one direct shot (most rules state a quarter sized glob of paint is considered "dead"), which is probably somewhat realistic. You could catch a lucky break though if the size of the paint glob isn't large enough.