History VideoGame / HalfLife2

*** Ceiling Turrets make their only antagonistic appearance inside the laser tripwire room of the Overwatch Nexus in “Follow Freeman”. However, they cannot be destroyed and are only used to kill the player if they touch a laser. Ground turrets likewise make their only appearance in this building and are similarly triggered, but are destroyable.

-->"Now... ''[removes mask]'' About that beer I owe ya."

** The crossbow shoots red-hot metal bars normally used to reinforce concrete.

* GenreShift: Played with. The game briefly turns into SurvivalHorror during the chapter "We Don't Go To Ravenholm...", where your main enemies are headcrab zombies. You're encouraged to make use of the gravity gun and use objects as your weapons(many of them being dirty sawblades). At the end of the chapter, the game returns to action, as you find yourself fighting Combine soldiers.

* GunsDoNotWorkThatWay: A minor example. The shotgun (a SPAS-12) has a secondary firing mode that fires two shells at once. Seems like someone mistook the tubular magazine below the barrel for another barrel.

** The Gravity Gun is reasonably powerful and perhaps ''the'' most versatile weapon in the game with a variety of uses: if you are in any situation where there is a physics-enabled prop, you have ammo for it. ''Episode One'' even has an achievement for only firing regular guns a single time, to ShootOutTheLock immediately after getting the pistol again.

** ''Episode Two'' gives you a healthy cross-section of your arsenal within the first few minutes, giving you the shotgun and revolver very soon after the expected crowbar and handgun. The dev commentary confirms this was intentional, fully expecting that most players would have already played through the main game and ''Episode One'' and determined their preferred weapons by this point.

* TenSecondFlashlight: Played straight, where it shared the same energy meter as [[SprintMeter sprinting]] and [[OxygenMeter holding your breath]]. In the original game the flashlight had its own meter, and it was given one again in ''Episode Two''. In the latter case, the light recharges pretty quickly, but it takes ages for them to run out. Lampshaded too, as Alyx may give a snarky remark that you really need to get Dr. Kleiner to give you a new battery for it.

** The "consoling couple" from ''Half-Life 2'' have shown up twice in the game (once before the apartment raid, the second during the Uprising), and once in both Episodes.

* TooAwesomeToUse: First obtained after Ravenholm, the Pulse Rifle has some shades of this in ''Half-Life 2''. A completely filled 90-round magazine deals a lot of damage and is relatively versatile in multiple ranges, but it often demands careful usage because its ammo is unreliable to find until the last few chapters, where practically every second mook is toting one.
* TrainingDummy: The disabled Strider at the end of ''Episode Two'', as well as a dead Combine soldier tied to a post after you get the pheropods in ''Half-Life 2''.

* DreamIntro: "Rise and shine, Mr. Freeman. Rise and... shine." This occurs at the beginning of the second game after Gordon Freeman was put into storage stasis by the G-Man. Upon awakening, he is met with the mysterious and very dreamlike image of the G-Man, who attempts to awaken him with a cryptic message.

* HeroicMime: Lampshaded repeatedly in the second game.

** The Razor Train [[{{pun}} fares]] even worse. It's extremely tall. There's really no loading gauge in the world it would fit in. Unless the Combine built a specific lines just for those, they're completely useless. The train seems to be freight in nature but judging by its single-axled [[https://en.wikipedia.org/wiki/Jacobs_bogie Jacobs bogies]] it's apparently a multiple unit which are known to consist of fixed amount of permanently cupled cars which would be totally impractical for a freight train. They also seem to be very limited to what kind of cargo they can haul.
** After getting out of the mines you'll meet the only flat car in the game, which turns out to be much wider than the loading gauge would allow. Also many of the box cars bogies exceed the edges of the cars which makes it impossible to couple them. Not that there are any couplers on them in the first place.

* MaleMightFemaleFinesse: Gordon Freeman and Alyx Vance. The audio commentary for ''Episode One'' says that the reason Alyx can jump and climb better than the player is that she's more athletic while Gordon's more heavily built (and wearing Powered Armour, of course).

* RememberTheNewGuy: Barney, Kleiner, Eli, and Breen, as well as Magnusson in ''Episode Two'', are introduced as people that Gordon knew from his time at Black Mesa. Most prevalent in the cases of Breen and Magnusson, who did not have counterpart models in the original game they could tie back to.

** Alyx appears to have an electronic one about half-way through ''Half-Life 2'', which opens all doors in Nova Prospekt and can also hack Combine computer consoles.

* SmartGun: Pulse Rifles, a Combine invention, have a built-in mechanism that replaces the energy cells that power the gun when the user needs to reload. It has one of the faster reloads in the game, especially considering its high damage per magazine.

* ArtisticLicensePhysics: The superheated rebar crossbow wouldn't penetrate very well in real life, as red-hot steel is soft and would deform on impact rather than penetrate anything.

* TripodTerror: Striders and Hunters. The Striders are the Combine's heavy assault monsters and are used when a Dropship or Gunship would be impractical, such as urban combat and protecting the Citadel. Hunters are used as scouts and escorts for both Overwatch soldiers and Striders and are extremely tough against most attacks and their brains are a quick as their feet though blunt force trauma from a Gravity Gun or a muscle car ramming them can quickly kill them.

* TheQuisling: Wallace Breen, who sold out the human race to the Combine. The page quote is from one of his speeches.

* PetMonstrosity: Lamarr. "She"'s de-beaked but doesn't mean she'll willing to listen to Dr. Kleiner when the room erupts into activity.

** After getting out of the mines you'll meet the only flat car in the game, which turns out to be much wider than the loading gauge would allow. Also many of the box cars bogies exceed the edges of the cars which makes is impossible to couple them. Not that there are any couplers on them in the first place.

* GoddamnBats: [[InvokedTrope Invoked]]. The commentary for the Episodes notes that Poison Headcrabs were found to be perfect for scaring the player, without actually being a threat, as they will bring Gordon's HPToOne, but can't kill him and his HP is restored to what it was before rather quickly.

''Half-Life 2'' is a first-person shooter released in 2004 by Creator/{{Valve|Corporation}} which serves as the sequel to their revolutionary and critically acclaimed debut title ''VideoGame/HalfLife1'', and is the second mainline title in the ''VideoGame/HalfLife'' series. It broke new ground on many fronts in its graphics engine, physics system, artificial intelligence, and its online distribution/updating system. Unlike the previous game, it did not include a multiplayer mode on its own; instead, every retail copy of the game also came with ''VideoGame/CounterStrike: [[UpdatedRerelease Source]]'' to help fill out the multiplayer side of things.

** In Episode 2, when the player has to drive around to defend the rocket from Striders, a radar is installed to show which direction the car is, should they get separated.

Until on November 21, 2019, over 12 years after the release of ''Half-Life 2: Episode Two'', [[SavedFromDevelopmentHell a follow-up was finally announced]], but not necessarily the ones that fans had expected. The next installment of the series was revealed to be a title for [=SteamVR=] called ''VideoGame/HalfLifeAlyx'', an {{Interquel}} set between ''Half-Life'' and ''Half-Life 2'' involving Alyx and her father taking the fight to the Combine. [[spoiler:And ''Alyx'' ends with a genuine SequelHook proving that, yes, ''Half-Life 3'' [[AscendedMeme is finally confirmed]].]]

Until on November 21, 2019, over 12 years after the release of ''Half-Life 2: Episode Two'', [[SavedFromDevelopmentHell a follow-up was finally announced]], but not necessarily the ones that fans had expected. The next installment of the series was revealed to be a title for [=SteamVR=] called ''VideoGame/HalfLifeAlyx'', an {{Interquel}} set between ''Half-Life'' and ''Half-Life 2'' involving Alyx and her father taking the fight to the Combine.

* CallBack: One of the things you can do in the original ''Half-Life'' before putting on your HEV suit and starting the experiment is visiting the employee break room, which contains a microwave oven. Repeatedly pushing the buttons on it (which many players did due to the satisfying 'beep' it makes) will eventually make the microwave casserole explode and cover the interior of the microwave as another scientist asks Gordon what he's doing. Over twenty years later in ''Episode Two'', Doctor Magnusson still holds a grudge over that casserole.

* HoldTheLine: Numerous instances where you have to hold off foes to wait for an elevator or some such (unfortunately, the game loves as well to use scripted events where it throws you infinite enemies until you do ''something'', and often it's hard to tell which of the two situation you're facing against). A stand-out is the final battle in ''Episode Two'', killing Striders before they can fire upon and destroy a satellite rocket stationed at White Forest. Optionally you can keep them from destroying the smaller buildings as well for an achievement.

** Antlions will respawn forever from the ground or holes in the pavement; in ''Episode One'' you are able to plug up the holes by shoving cars onto them with the gravity gun. One of the [=NPC=]s even hangs a lampshade on this: "It's [[StealthPun spawning season]] for the Antlions!"
** In general, the game ''loves'' to use scripted events where it throws you infinite enemies until you do ''something'' (usually moving to a specific spot to activate a trigger). Often, it's hard to tell when it's one of these moments, and when it's supposed to be a HoldTheLine moment. Sometimes, you'll waste lots of valuable ammo against a horde of respawning enemies. Sometimes, you'll frantically look for a (non-existing) trigger that will stop the horde of (supposedly) respawning enemies.

** In general, the game ''loves'' to use scripted events where it throws you infinite enemies until you do ''something'' (usually moving t a specific spot to activate a trigger). Often, it's hard to tell when it's one of these moments, and when it's supposed to be a HoldTheLine moment. Sometimes, you'll waste lots of valuable ammo against a horde of respawning enemies. Sometimes, you'll frantically look for a (non-existing) trigger that will stop the horde of (supposedly) respawning enemies.

** "That's the old passage to Ravenholm...we don't go there anymore." Guess where you're headed?

** Whenever you encounter enemies that are only vulnerable to the rocket launcher, there will be a crate near by that provides endlessly respawning rockets, as otherwise it would be [[UnintentionallyUnwinnable impossible to destroy the enemy in question if you ran out.]]

* TheBerserker: The Shotgun wielding combine soldiers, distinctive for their orange shoulder patch, [[RedEyesTakeWarning red goggles]], and their reckless disregard for personal safety when rushing you. They are dangerous enough to be able to kill Alyx Vance, whose rapidly regenerating health is usually enough to render her invulnerable. They are introduced in ''Episode Two'', but have been retroactively inserted into the previous games.

** [[https://github.com/Jackathan/MarcLaidlaw-Epistle3/blob/master/Epistle3_Corrected.md The plot of Episode Three released by Marc Laidlaw]] [[spoiler: has Gordon and Alyx destroy the Combine homeworld with the Borealis in a planned suicide attack, but they are taken to safety by the Vortigaunts and the G-Man, respectively. Although Gordon is free, Alyx is implied to be G-Man's newest pawn, and Gordon has been flung far enough into the future that the terrain itself has changed. The future of humanity is also left open ended, with Gordon unsure of whether or not the resistance has succeeded in driving out the Combine.]]
* BlindingCameraFlash: The scanner enemies do this if you're looking at them when they photograph you (this is the only hazard they pose, apart from occasionally giving your position away to a strider or suicide-rushing you when they've taken sufficient damage). Revisited in a much deadlier fashion in the Episodes as the Advisors' mental attack is displayed onscreen as a visual distortion.

* DesolationShot: Used extensively in the Episodes, most prominently with the ruined city blocks glimpsed when emerging from underground in ''Episode One'' and the view of the destroyed Citadel at the beginning of ''Episode Two''.

* DirtyCop: Civil Protection is composed of un-augmented humans that joined for more privileges or out of sympathy for the Combine and take full joy out of beating up defenseless citizens. One tosses a can on the ground just to make Gordon pick it up(and laughs at him when he does). If Gordon tosses at him, he beats him with a stun baton. Barney also claims that he's "way behind on [his] beating quota", although this is most likely a joke in reference to the brutality of the police.

* IdiotBall: Gordon Freeman climbed inside of a moving metal coffin in the Citadel just because he had no clue where else to go. ''Twice''. [[StupidityIsTheOnlyOption Not that he had much in the way of other options]], but still...

* IronicEcho: Midway through the game, Breen dismissively ends his conversation with [[spoiler: Dr. Mossman]] by saying "So sorry [[spoiler: Judith]], I'm all out of time." Later, when she turns on him and he's pleading with her, she says "I'm sorry Wallace, you're all out of time."

** In general, the game ''loves'' to use scripted events where it throws you infinite enemies until you do ''something''. Often, it's hard to tell when it's one of these moments, and when it's supposed to be a HoldTheLine moment. Sometimes, you'll waste lots of valuable ammo against a horde of respawning enemies. Sometimes, you'll frantically look for a (non-existing) trigger that will stop the horde of (supposedly) respawning enemies.

* ScrewThisImOuttaHere: In ''Episode One'' Barney states that the main obstacle between the rebels and the train station were mostly Metropolice who were getting second thoughts about defending the city.

* ShoutOut: Lamarr the Headcrab -- Hedy Lamarr (get it?) was a well-known, glamorous actress between about 1940 and 1960 (and, incidentally, also co-invented an early form of spread-spectrum wireless communications), but she's probably better known for suing Mel Brooks for naming the main villain of ''Film/BlazingSaddles'' "Hedley Lamarr." So what if we name a de-fanged brain-devouring parasite after her...
** Hedy Lamarr is probably known even better for being one of the first women ever that appeared fully naked in a movie (''Extase'', a Czechoslovak film directed by Gustav Machaty in ''1932''). Naming a pet headcrab after her can be viewed as way more disturbing than the previous reason.
** Dr. Breen's name may or may not be a reference to ''WesternAnimation/AeonFlux'' as the people of antagonist Trevor Goodchild's nation of Bregna are called "Breens".
*** His name is also similar to notorious rapist and pedophile Walter Breen, husband of Creator/MarionZimmerBradley.

** The way Dr. Kleiner says "Great Scott" is similar to [[Franchise/BackToTheFuture another scientist famous for saying that phrase.]]
*** There also happens to be a box of plutonium under Dr. Kleiner's desk.

* ShutUpHannibal: Sort of: you can use the Supercharged Gravity Gun to either rip out or just blast the Breencasts. The last one is harder to silence, since Breen does it on an unbreakable screen... but luckily for you, there's a few of the Combine high-energy balls nearby which can be fired at it with the Gravity Gun if you ''really'' don't want to listen to him.
* SkeletonKey: Alyx appears to have an electronic one about half-way through ''Half-Life 2'', which opens all doors in Nova Prospekt and can also hack Combine computer consoles.

* StealthPun: Lamarr the headcrab, which is just obscure enough a reference that it can be missed. Explained in a blink-and-you-miss-it comment by Kleiner after you leave his lab for the second time that her first name is actually [[spoiler:Hedy]].
** Not many people realise that [[UsefulNotes/RasputinTheMadMonk Rasputin]] was known as Father Grigori - given that Half-Life 2's Father Grigori [[RasputinianDeath just won't die]], he might actually ''be'' Rasputin.

* StupidityIsTheOnlyOption: During a certain point in the Citadel level the player is left no choice but to [[spoiler:climb into a Stalker pod in order to advance. And after being (of course) captured, stripped of your weapons, and escaping due to a DeusExMachina, you are later required to step into another, identical, pod, ''and be captured again''. {{Lampshade|Hanging}}d by Breen, who congratulates you for delivering yourself to him so conveniently.]]

* SuspiciousVideogameGenerosity:
** Your protective suit has 100 points of armour when fully charged, and the wall chargers can give you 75 points (on easy). When you make it into the Citadel at the end of the game, the wall charger charges your armor up to 200 points, and they can fully charge your health as well (before you needed separate health stations that were usually but not always right next to the suit chargers, and which also only gave 75 health total). Uh-oh.
** During the "Our Mutual Fiend" chapter of ''Episode Two'', the valley's buildings are not only equipped with respawn points for Magnusson devices, the shelves also restock with batteries and medkits to keep you alive as you fight the numbers of Hunters and Striders outside.
%% ''WebComic/{{Concerned}}'' pointed this out a [[http://hlcomic.com/index.php?date=2005-11-04 couple]] [[http://hlcomic.com/cast.html times]].
* TacticalSuicideBoss: The Hunter Chopper encountered in ''Episode Two'' can only be killed by throwing its mines back at it with the gravity gun, since it's ImmuneToBullets and you lack explosives.

** After hooking back up with Barney during the rebellion, he has a flashback about it. Whatever happened, it must have been traumatic, as he was plainly traumatized.
*** Barney is probably wary of teleporters because he personally suffered a teleporter accident at the end of Blue Shift, though he got better.

* ThereIsNoKillLikeOverkill: Hinted at by Dr. Breen in the Combine Teleporter. "You, on the other hand, will be destroyed in every way it is possible to be destroyed, and in some ways which are essentially ''impossible!''"

* TrapMaster: Father Grigori has dozens of traps littered around Ravenholm for the sole purpose of killing headcrab zombies.
* TrialAndErrorGameplay: The White Forest defense isn't so bad itself, but ''Episode Two'' has an achievement for getting through the entire segment without losing a single building. This can be problematic because sometimes Striders will spawn as sprinting variants that charge their target building and then immediately destroy it, and the game will create situations where it'll spawn a slow Strider to get the player's attention before deploying a fast one to wipe out a building before the player can even get close to it, if they engaged the slow Strider already. And this exact setup happens with the very first two Striders that attack the base. Better make it a habit to manually save religiously, or look up a guide on what Striders will spawn from where.
* TriggerPhrase: [[spoiler: Not exactly a phrase, but the silhouette of the G-Man appearing on a monitor causes Alyx to go into a trance and deliver a message to her father. She has no memory of this. Makes one wonder how much control the G-Man has over her.]]

* VideoGameVista: At one point during the early stages of ''Episode Two'', you're required to take a look at the scenery towards the destroyed City 17, an event that prompts a resonance wave that removes a fence and allows you to continue.

* VillainousBreakdown: Doctor Breen's broadcasts show him growing increasingly short-tempered, until he finally snaps and begins haranguing Gordon directly.
** Coming to a logical conclusion after he realizes you're right on his tail.

** The seesaw puzzle in ''Route Kanal''. There was no reason to have it other than to show off the engine. All Gordon does it put a bunch of cinder blocks on one side to lift it up; much like the similar see-saw bridge for no reason in the first level of ''VideoGame/SuperMario64'' eight years prior, the fact that the team could do it was impressive at the time.

* YouFool: [[spoiler:Doctor Breen]] yells this when [[spoiler:Gordon Freeman starts breaking the teleporter]].

* ArtificialStupidity: Resistance fighters in ''Half-Life 2'' are actually pretty good A.I.-wise (they strafe/use cover, verbally recognize different enemy types (i.e. "Combine!" "Zombies!"), and are smart enough to back away from melee enemies while firing), but they do have an annoying tendency to charge straight into sniper rifle fire, [[NoSenseOfPersonalSpace cluster around each other and the player]] instead of giving anybody some space to breathe (or run away from a tossed grenade), and cannot be told to "wait" in a safe position for more than several seconds before rushing in to crowd around the player again.
** There is also the infamous "[[https://www.youtube.com/watch?v=e0WqAmuSXEQ barrel trick]]" from early in the Water Hazard chapter, where a certain Metrocop turret-gunner can't see you if you can't see him - say, if you carry a barrel or even a paint can so that it obstructs your view of him.

* ArtisticLicenseEngineering: Apparently the Combine do not know ''hand brakes'', which is why they have to secure their [=APCs=] using wooden stop blocks. Just so Gordon could knock them away with his Gravity Gun to send the vehicle down a cliff.

* BittersweetEnding: ''Episode Two''. [[spoiler:Yes, the Resistance defeated the Combine assault on White Forest, ''and'' closed the superportal. But Eli is killed by an Advisor in the Resistance's moment of triumph, his last words desperately telling his daughter to look away. Alyx and Gordon survive only due to [=D0G=]'s counterattack, and the game fades to black as Alyx cries over her father's body.]]

* DevelopersForesight:
** The Source engine is ''remarkably'' future-proofed, with out-of-the-box full support for ultra-widescreen aspect ratios, 4k resolution, and high refresh rate monitors, all in a game made in ''2004''. Even the most advanced other games from that era, like ''[[VideoGame/UnrealIITheAwakening Unreal II]]'', ''VideoGame/FarCry1'', and ''VideoGame/Doom3'', need fan-made external fixes to support many of these features. Hell, many ''modern'' games don't have some of these features.
** At the end of "Point Insertion", Gordon is trapped in a tiny room after the stairs he climbed down collapsed under his weight; he is subsequently knocked out by a swarm of Civil Protection officers before Alyx saves him. If the player somehow finds a way to stay at the top of the stairs after it collapses, there are a pair of Civil Protection officers behind you who will ensure the scene goes as intended.
** After obtaining the gravity gun, if the player pulls the barrel down before Alyx says to try pulling them down, she skips the mention of the barrels and instead says "Try pulling something towards you".
** In ''Episode Two'', if the player manages to get through a small crevice past the antlion guard, there is floating text that reads "How did you get here?" further into the cave.

** Also in the comment that it is spawning season for the Antlions. Very possibly in G-Man's warning to Eli (by way of his daughter) to prepare. White Forest's successful shutdown of the superportal [[spoiler:led directly to Eli's death]], after all.

* GoddamnBats: [[InvokedTrope Invoked]]. The commentary for the Episodes notes that black headcrabs were found to be perfect for scaring the player, without actually being a threat, as they will bring Gordon's HPToOne, but can't kill him and his HP is restored to what it was before rather quickly.

** Did you know that the Tau Cannon can charge its shots? If you didn't play Half-Life you wouldn't!

* HeroicSacrifice: Father Grigori, possibly, as towards the end of chapter 6 in ''Half-Life 2'', he tells you to move on [[YouShallNotPass while he buys some time]]. It's possible that he was overrun by Headcrab Zombies and died, but [[HolyHitman given how good he is at killing Zombies]], it's also possible that he lived. If you stick around to watch the battle, he adamantly refuses to die in front of you no matter how long you linger.

* HoistByHisOwnPetard: You can one-shot Hunters by [[spoiler:catching their darts with a physics object and shooting it at them]].

* HoldTheLine:
** Numerous instances where you have to hold off foes to wait for an elevator or some such. A stand-out is the final battle in ''Episode Two'', killing Striders before they can fire upon and destroy a satellite rocket stationed at White Forest. Optionally you can keep them from destroying the smaller buildings as well for an achievement.

* HolyHitman: Father Grigori.

* IdiotBall: Gordon Freeman climbed inside of a moving metal coffin in the Citadel just because he had no clue where else to go. ''Twice''. [[StupidityIsTheOnlyOption Not that he had much in the way of other options.]]

* InvoluntaryGroupSplit:
** Happens at the end of "Black Mesa East", when the Combine shells the hideout and causes a cave-in.
** Recurs during "Anticitizen One", when [=D0G=] opens a Combine barrier then is carried off by a troop transport, then again when Alyx later scales a building to spot the means for much less monkey-like Gordon to progress by and is promptly captured by a Combine patrol.

* JustTrainWrong: So many examples to point out. When you first arrive in City 17 not only is the passenger car ridiculously short, it also has door only on one side. The platforms are absurdly low and to cover the clearance there is a small stairway which the train is required to stop exactly so the door would be aligned with it. The platforms are also laughably short unable to serve any train of significant length. If you inspect the train closely, you'll find out it [[https://www.trainsingames.com/img/hl2/picoupling.jpg doesn't have any couplings]]. The [[https://www.trainsingames.com/img/hl2/pioutside.jpg locomotive]] is derived from the [[https://en.wikipedia.org/wiki/DR1_diesel_train DR1]] which isn't a locomotive but a self-propelled car of a DMU. Now if you turn your attention to the tracks - they are really poorly made. They're absurdly crooked, not even trying to imitate proper curves, switches connecting in weird angles which would make any train derail at the mere sight of them. Some of the tracks are just plain, flat 2D lines with some reflection thrown in there to hide it. The switches are arranged in a way that makes no sense, preventing any meaningful operation in the trainyard. There are also randomly scattered freight cars apparently only to get in your way and utterly destroy any remaining hope for this game's rail works to serve any purpose.

** In Episode Two there are some more freight cars to be seen. Their bogies are ludicrously oversized. So much in fact that the couplers are attached to them instead of the cars' frames. On top of that the wheel sets are actually wider than the tracks so they don't even sit on the rails which again are just a 2D texture.
* LampshadeHanging: A quarter of the Vortigaunt's lines in ''Episode Two'' are poking fun at the game's own use of tropes, such as the prevalence of {{Broken Bridge}}s or Gordon's habit of falling into pits. Examples include, "Pity the generator that requires a Vortigaunt to operate," "No pit would be complete without a Freeman climbing out of it," and, "What next in the parade of constant obstacles?"

* LaughingMad: Father Grigori has had to witness numerous horrors in his time in Ravenholm, and his way of powering through the negative emotions that generated in him is clearly to laugh maniacally.

* LeftHanging: ''Episode Two'' [[spoiler: ends on a cliffhanger, with Alyx's father apparently dead and she and Gordon at the mercy of the villains]], which may be left unresolved if the ''Episode Three'', now delayed well into its second ''decade'', remains {{Vaporware}}.
** [[spoiler: VideoGame/HalfLifeAlyx actually addresses this last point, giving it a big fat SequelHook.]]

** The Hunter Choppers, who instead of being [[StandardFPSEnemies Heavies]] like the Hunters or BossInMookClothing like the Guards, are straight bosses themselves. They are far superior to any other vehicle or Synth the Combine can field. They fly, move extremely fast, can eat up much more damage than an [=APC=], and come armed with an unerringly accurate and powerful pulse machine gun and a seemingly unlimited supply of mines. Fortunately, they're rare (only two are encountered in the whole series thus far, three if you count the one in the playable cut beta episode ''Lost Coast'' ) and you're fortunate enough to encounter while they're on their own and you've already killed all mooks prior to fighting them.

* LoadsAndLoadsOfLoading: The Xbox 360 version keeps on pausing for [-LOADING-], sometimes ''in the middle of an area.''
* LooseFloorboardHidingSpot: In ''Episode Two'', one of the secret stashes is hidden in a small shed, but all you can find in said shed is a sawblade embedded in the floor. Soon after, a hoard of zombies attacks the player, and some might try to rip up the sawblade with the Gravity Gun for use as an ImprovisedWeapon, only to pull up the floorboard along with it, revealing a veritable jackpot of supplies hidden underneath. Though you'd need to break open the rest of the floor (ideally with the crowbar) to get everything.
* LoonWithAHeartOfGold: Father Grigori is clearly [[LaughingMad more than a bit unhinged]], but at the same time, all his actions toward you in-game are very much intentionally helpful, from giving you hints, to tossing you a shotgun to help fight the zombies, to enabling your escape from Ravenholm.
* LordBritishPostulate:
** The Hunter Chopper in "Water Hazard" is meant to be a PuzzleBoss, as you're not meant to destroy it until your airboat gets fitted with a cannon powerful enough to damage it. It ''can'' be damaged by the rocket launcher, but you don't get that until later, and the chopper has so much HP (5,600) that even if you give yourself the rocket launcher via cheats it would take an extremely long time to bring it down that way, but ultimately it's still possible.
** Prior to being patched out, it was possible to kill Eli Vance at the end of the chapter "Entanglement". Your weapons don't hurt him at all, but if you grabbed a sentry gun from earlier in the level, carried it all the way to Eli, and set it down facing him, it would quickly blow him away.
** The physics engine can be exploited to kill certain otherwise-invulnerable [=NPCs=] using the Gravity Gun and nearby physics objects, and done at the proper times, you can avoid triggering a NonstandardGameOver where you would otherwise receive one. [[https://www.youtube.com/watch?v=nhm-dPS3zM8 Observe.]]

* MadnessMantra: A 'passenger' in the trainstation at the very start at the game keeps repeating "...they're always departing but they never arrive... and the ones that do arrive, they-they never leave... you never see them go... they're always full... no one ever gets on... but they're always... they're always departing but they never arrive...", while pacing in front of a train schedule.

* MaleMightFemaleFinesse: Gordon Freeman and Alyx Vance. The audio commentary for the first expansion/episode says that the reason Alyx can jump and climb better than the player is that she's more athletic while Gordon's more heavily built (and wearing Powered Armour, of course).

* MetaGuy: The [[http://combineoverwiki.net/wiki/All-Knowing_Vortigaunt All-Knowing Vortigaunt]] in ''Water Hazard''. When Gordon interacts with him, he makes various cryptic statements about the Black Mesa Incident, the Xen, the G-Man, the [[spoiler: Nihilanth]] and [[spoiler: its death]], and Gordon's deep connection to the Vortigaunts, among other topics.

* MonsterMunch: In the third level in ''Half-Life 2'', the Combine start headcrab-shelling the outskirts of City 17 to try and kill Gordon. At one point you get to watch as a headcrab latches on to a civilian's head and turns it into a zombie (or MercyKill him before he gets assimilated, whichever floats your boat).

* NewWeaponTargetRange: You get the Gravity Gun right before you go to Ravenholm, which is full of saw blades, explosive barrels, and other things that are exceptionally fun to throw at the zombie hordes. Additionally, Zombies don't carry guns and thus your only supply of ammo is what you can scavenge from the environment - so not only is the gravity gun all but required for the level, it teaches you to use it and the environment to conserve ammo when necessary.

* NiceJobFixingItVillain: The confiscation field in the Citadel destroys all your weapons... except the gravity gun, which is made so powerful that it can vaporize a Combine Elite in less than 3 seconds and pick up/throw energy orbs, which are capable of doing even ''more'' damage.

* NoEnding: One of the essential complaints about the game, as time has gone on. ''Episode Two'' ends on a CliffHanger that, yes, deals with the ''immediate'' crisis but still leaves the larger conflicts of the game completely unresolved and a huge number of plot angles and character arcs unfinished.
* NoFairCheating: Early on in the game, when you are walking through the square without any weapons, [[{{Foreshadowing}} a Strider walks past in the distance]], behind a roadblock. If you put the cheat codes in and blast the Strider with the rocket launcher (which you don't normally have at this point in the game) as it passes, it pauses and glares at you for a moment before continuing on its way.

* NoSexAllowed: Noted early on in ''Half-Life 2'' when Breen reads a letter from a concerned citizen about the "Suppression Field" that keeps people from reproducing. Amusingly, later in the game you come across another "Suppression Device": A giant artillery-like laser cannon. That'll kill the mood alright.

* NoTranshumanismAllowed: Despite the fact the technology is available, and the situation desperate enough that cybernetic modification is rather plausible, only the Combine's human loyalists (who are even called the Transhuman Forces) have cybernetic upgrades of any kind... well, them and the Stalkers -- dissident (or just unlucky) humans mutilated into mindless cyborg drones. Even the Combine's "leader of humanity" hasn't upgraded himself, despite talking ''of his own free will'' about how the Combine are here to elevate humanity to the next stage. In fact, when the Advisor suggests uploading him into a host body, his initial response is "You must be joking!" Originally, Breen's place was taken by 'the Consul', who rendered himself immortal using the Combine's life support technology.
** It might have something to do with the fact that most Transhuman technology is currently under the use of the Combine and they take out the "Human" part of TransHuman.

* NotSoStoic: Although focused and professional most of the time due to thorough brainwashing, Combine soldiers have special voiceovers that play whenever the second-to-last soldier in a group is killed.

* OnceKilledAManWithANoodleImplement: In ''Episode Two'', a Rebel-in-Training at the White Forest Base first claims to have used [=AR3s=] (which don't exist), then claims to have killed Hunters (alien tripod cyborgs that are rather deadly) "with his own hands."

* ThePasswordIsAlwaysSwordfish: This exchange in ''Half-Life 2''.

* PleaseDontLeaveMe: [[spoiler:Alyx says this to her father after he's killed by an advisor.]]
* PoliceBrutality: Civil Protection officers are this trope to a T. In the first chapter of the game, [=CPs=] will shove you away if you stand next to them and will pull out their stun baton to wack you if you either persist or ''attempt to speak with them''. In one instance, a [=CP=] knocks down a can and forces you to pick it up, laughing when you do so. Then, of course, there are several times where you can witness [=CPs=] harassing or even assaulting citizens and using excessive force to arrest people. Somewhat justified as the whole game takes place on a VichyEarth.
* PostClimaxConfrontation: Happens in ''Episode Two''. After successfully fighting off a force of Combine Striders, the White Forest rocket launches safely and successfully closes the Combine superportal. It seems that you have achieved victory and you are heading off to find the Borealis, [[spoiler:that is, until Combine Advisors appear, pinning you against the wall and killing Eli, while you and Alyx helplessly watch. Thankfully, D0g appears, attacking the Advisors and forcing them to flee]].

* PrivacyByDistraction: Eli sending Alyx to make tea so he can tell Gordon about the G-Man.

* RailroadTracksOfDoom: You're driving a buggy down a train bridge, a stopped train taking up one of the two tracks. You're halfway across when you suddenly hear a blaring horn...

* RequestForPrivacy: Near the end of ''Episode Two'', Eli Vance asks his daughter Alyx to get him some tea, so he can reveal to Gordon his [[spoiler:acquaintance with the G-Man and his role in the Black Mesa Incident]], as well as ask him to destroy ''Borealis'' without trying to use it--something he obviously doesn't want Alyx to know beforehand.

* RespawningEnemies: Antlions will respawn forever from the ground or holes in the pavement; in ''Episode One'' you are able to plug up the holes by shoving cars onto them with the gravity gun. One of the [=NPC=]s even hangs a lampshade on this: "It's [[StealthPun spawning season]] for the Antlions!"
* ReverseEscortMission: ''Episode One'' has an underground level in which you must spend a part of it pointing a flashlight at enemies for Alyx to shoot them, as there was very little ammunition for you to use at first.
* RidiculouslyDifficultRoute: You end up having to go through Ravenholm (a zombie infested town on a route that "no-one uses anymore") because the other route you were originally going to take gets cut off by the Combine attack.

* ClimacticElevatorRide: The game has Gordon and Alyx ride up an elevator before the final battle. Alyx takes this time to say a few things.

* CrazySurvivalist: The LaughingMad Father Grigori. Except that he's nice.

* CuttingTheKnot: In Chapter 4: ''Water Hazard'' a gate blocks your path so you're supposed to exit your boat and go through a building full of Metrocops to reach an explosive barrel and shoot it, so a hanging pile of metal beams will swing and break the gate. Or you could just use your pistol to shoot the barrel from really far away and skip the building entirely. The only reason to get out is to get some grenades.

* DiscOneFinalDungeon: "Entanglement". After the treacherous Dr. Mossman slips into the teleporter and teleports herself and Eli away, Gordon has to [[HoldTheLine defend Alyx from several waves of Combine soldiers using several reprogrammed Combine turrets]], while she tries to reroute the teleporter(which takes forever). After they teleport out, they find out that the teleport destroyed Nova Prospekt in the process and sparked the Uprising. Not only that, but they were teleported ''one week into the future''.

* DisintegrationChamber: The Combine [[NewSpeak sterilization chamber used for the excision of quarantined malignants]] within the City 17 Citadel. This is done by a track of prisoner transport coffins that run throughout the entirety of the place and you happen across a loading platform for two tracks with one that loops through one of these chambers. Climb on in if you want to [[PressXToDie Press E to Die]]!

* DroughtLevelOfDoom:
** Ravenholm is a zombie-infested ruin without much ammo. The player is, however, provided a wide range of sawblades, explosives and environmental traps to use against the zombies instead, to get them used to the combat applications of the Gravity Gun they were just given. There is even an achievement for getting through Ravenholm using only the Gravity Gun.
** ''Episode One'' has the chapter ''Lowlife'', set mainly in abandoned highway tunnels and parking lots beneath City 17, which have even less in the way of ammo and other supplies than Ravenholm. To make matters worse, the tunnels are swarming with Antlions in addition to hordes of zombies. Be prepared to rely on Alyx to do a lot of the fighting for you.
* DualBoss:
** A pair of Gunships acts as a dual miniboss in the Nova Prospekt courtyard. Two more Gunships show up while Breen is trying to teleport away at the end of the game, but fighting them is completely optional as they're only there to impede you from destroying the teleporter.
** The first boss fight in ''Episode Two'' is a fight against an Antlion Guard and Antlion Guardian (without the usual poison effect on its attacks, making it no different from its standard counterpart) [[FlunkyBoss and their normal antlion minions]]. They don't hesitate to attack you at the same time, but you've got a healthy supply of SMG and Shotgun ammo, a safe spot where they can't strike you, and several exploding barrels lying around the valley...
* EasyLevelTrick: If you plan on getting the achievement "Zombie Chopper"[[note]]Beat Ravenholm using only the Gravity Gun[[/note]], consider bringing [=D0G=]'s ball in from the previous level. It never breaks after being launched with the Gravity Gun, its medium size means it's easily portable through doorways, and it deals enough damage to one-hit kill everything except poison zombies, which are all good traits on normal launchable objects. But it also has unique properties, like [[DrawAggro drawing aggro from enemies]] and being borderline unlosable between the noise it makes and its Rollermine AI's ability to follow Gordon. The only caveats are that it can get killed by explosions and it can't be brought into the cemetery due to an invisible wall, but the former only means the player needs to be a little careful with explosives and the latter is barely an issue since the cemetery is near the end of Ravenholm.
* {{Egopolis}}: New Little Odessa, the Resistance base run by Odessa Cubbage.

* AbandonedHospital: One of the settings in ''Episode One'', which appears to have been taken over by the Combine and, from the looks of things, is in the process of being abandoned ''again''.

* ArbitraryMissionRestriction: In ''Half-Life 2'' and ''Episode One'', striders are destroyed using the rocket launcher. In ''Episode Two'' they are destroyed using the just-introduced Magnusson device, apparently for no other reason than so that Valve could claim to have one new weapon in the game. Granted, you still ''can'' use rocket launcher, but it's too time-consuming for a time-critical mission.
* ArtifactMook: Headcrabs (and the Zombies they create) appear to be a case of this, as at first they're found mostly in places where the Combine have specifically used them as a biological weapon, launching them via artillery shells into Resistance settlements, but after Ravenholm, they often appear in the absence of these shells, becoming more or less just goombas ready to pop out of any vaguely abandoned area. It's not out of the question, however, that these are actually leftovers of the portal storms caused by the Black Mesa incident; ''VideoGame/HalfLifeAlyx'' corroborates this by showing that entire districts of City 17 are swarming with Headcrabs and other creatures from the Xen borderworld against the Combine's wishes.

* BadassInDistress: Near the end of the game [[spoiler: Gordon Freeman]] gets himself trapped in the bad guy's lair along with [[spoiler: Alyx Vance]] because he [[TooDumbToLive stupidly locked himself in a metal coffin.]] Not that he [[StupidityIsTheOnlyOption had any choice]].

* BlackoutBasement: ''Episode One'' has the third chapter, Lowlife. It's so dark that Alyx constantly needs Gordon's TenSecondFlashlight and flares found on the floor to target enemies.

* BookEnds: Half-Life 2 begins with the G-Man depositing Freeman onto a train entering City 17. It ends with G-Man "getting off" as one would a train.

* CatScare: [[TheGoomba Headcrabs]] are often placed in dark corners or hidden behind debris to jump and deal ScratchDamage, and serve no other purpose other than to surprise the player in otherwise safe areas. It's particularly cruel when Poison Headcrabs are used, which make distinct rattling and screeching sounds and have a bite that wipes your HP to its very bottom (Which heals back anyways). One example of this is when you finally escape Ravenholm via the mineshaft, where the player is likely sick and tired of fighting hordes of zombies and Headcrabs, and as you exit towards the fresh morning there's the dreaded sound of a single Poison Headcrab coming up behind you as your sendoff.

* TheComputerIsACheatingBastard: ''Inverted''. Your go-to medium range weapon, the Pulse Rifle, does almost 3 times as much damage in your hands as in an enemy's for no real reason, and its [[HyperDestructiveBouncingBall secondary fire]] instantly vaporizes anything but you and plot-important friendlies. In that case, it only does a negligible 15 damage.

* CoolBoat: An airboat that can ''run on land''. Mounted with an infinite ammo gun that was ripped off an attack helicopter.
** The Mudskipper is specifically equipped with it to take down the one(s) that caused such grief during the earlier parts of Water Hazard. As the Railroad Rebel says, "I like to bring a little irony to a firefight." If you don't monkey with it, the recharge and firing periods are the same as the hunter chopper, but you do a lot more damage to things with it than is done to you, just as with the [=AR2=] in the above listing.

* AbandonedPlayground: During the introductory wander through City 17, a playground is encountered, providing not only an opportunity to show off some of the physics features, but also to [[NightmareFuel hear a faint echo of children playing]].
* AbnormalAmmo: The crossbow shoots red-hot metal bars normally used to reinforce concrete.

* AdvancingWallOfDoom: The articulated, sectional wall near the escape from Nova Prospekt. Quite possibly the most literal example imaginable. And if you can't spot the only serviceable exit [[spoiler:on the left just before the lamp]], the wall will lift up a section, step forward and drop down. There's widespread evidence that an identical wall around City 17's citadel has been annexing an ever increasing area of the city, but nobody ever seems to directly notice it as out of place.

* AllAnimalsAreDogs: [=D0G=] himself, whose morphology is (at least by now, after all the modification Alyx has been doing to him) much closer to that of a great ape, but still retains the doglike behavior Eli had programmed into him. [=D0G=] is a GentleGiant.

* {{Antepiece}}:
** As described [[http://www.destructoid.com/untold-riches-the-brilliance-of-half-life-s-barnacles-233589.phtml this article]], there's a part early in the game where you need to push some barrels aside to move forward; doing so causes them to roll down a slope and get caught by a Barnacle. This cues the player into learning that Barnacles will snare physics objects, testing their knowledge when they're given a similar situation with an explosive barrel to kill multiple Barnacles at once.
** The Combine Rollermines introduced during ''Highway 17'' might remind players of a dangerous version of [=D0G=]'s ball, being shaped the same and pursuing Gordon in a similar way. The best way to kill them is the same as how the player first interacted with [=D0G=]: using the Gravity Gun to punt them away, preferably into the ocean or an enemy.

* BadassPreacher: Father Grigori. Whether or not Grigori is actually an ordained priest was [[UnreliableNarrator intentionally left ambiguous]]: he's one hundred percent LaughingMad. The crude but effective traps he designed and built all over Ravenholm offer little evidence either way — priests have historically had enough education and free time to do a lot of tinkering and inventing.

* BattleAgainstTheSunset: Gordon Freeman's final showdown with the APC chopper that has been tormenting him for much of "Water Hazard" in the chapter's final map, occurring in a partially depleted reservoir at Golden Hour

* BleakLevel: There are several very, very good reasons "We Don't Go To Ravenholm".

* VideoGameVista: At one point during the early stages of ''Episode Two'', you're required to take a look at the scenery towards the destroyed City 17, an event that prompts a resonance wave that removes a fence and allows you to continue.

* SweaterGirl: Dr Judith Mossman.