Half-Life Character Index
Player Characters | Supporting Characters | Xen Aliens | The Combine | Other Antagonists
Player Characters | Supporting Characters | Xen Aliens | The Combine | Other Antagonists
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Nihilanth
Nihilanth
Appearances: Half-Life | Half-Life: Decaynote |
"Alone... not you alone... not you alone..."
Voice Actor: Michael Shapiro (Half-Life 1)
"FREEEEEMANNNN..."
The ruler of the Xen aliens and the main antagonist of the first Half-Life (and by extension, Blue Shift, Decay and part of Opposing Force). His race was under severe threat from the Combine, being hunted to near extinction. Sometime prior to the first game, he enslaved the Vortigaunts, who were further pursued by the Combine. To escape them, he and the Vortigaunts fled to the border world, Xen, where they set up shop. Still desperate, he used the Resonance Cascade to launch an invasion of Earth, and despite the Black Mesa's scientists' best efforts to plug the rift between the dimensions, he was able to use his psychic powers to force it to stay open. His forces had success with pushing back the HECU, but his invasion was ended when the Black Ops nuked Black Mesa and Gordon Freeman traveled to Xen and killed him, finally closing the hole in the dimensions.- 0% Approval Rating: Just like the very beings he escaped from, the Nihilanth is unmourned by those he abused after his death. Very few if anyone mentions him ever again after the events the first of Half-Life game. And those few mentions that do post-mortem, are just reminder of how much a horrible tyrant he was.
- Always a Bigger Fish: Invoked by Nihilanth. He's undoubtedly talking about the Combine, or more specifically the Combine Advisors — or, quite possibly, who they're advisors to.
- Ambiguously Evil: Mostly because we know so little about him; what we do know casts him in a pretty ambiguous light. On one hand, he did enslave the Vortigaunts and invade Earth, with his forces being quite indiscriminate in their killings. On the other hand, the Black Mesa scientists had repeatedly invaded Xen to take apparently valuable crystals and specimens (including actually sentient soldiers in the Nihilanth's army), and Marc Laidlaw confirmed that the Nihilanth's invasion of Earth was largely an act of desperation, as his kind had been hunted to near extinction by the Combine. He also seems to care somewhat about Xen's ecosystem, given his apparent horror in the telepathic message he sends to Gordon after Gordon kills the Gonarch ("Doooone... what have you dooooone?"), and was the only thing keeping the Combine from invading our universe. That said, read Moral Myopia below.
- Arch-Enemy: Possibly he considers himself this to Gordon and the Combine as a whole. He acknowleges Freeman's name in transparent fury at the final battle and he seems in despair over being the last remaining member of his species.
- And There Was Much Rejoicing: Given that he was a slaver who is implied to have been oppressing the Vortigaunt kind for eons, his loss is not particularly mourned by his Vort kin."We bear witness to the bright eternity of the Nihilanth's demise."
- Attack Its Weak Point: The only way Freeman can kill the Nihilanth is to fire everything he's got directly into its brain. Even then, it takes quite a bit of damage.
- Big Bad: Of the first game, and by extension, Decay and Blue Shift.
- Big Bad Ensemble: Between himself and his forces, Race X, the HECU, and the Black Ops in the first game and its expansions.
- Black Eyes of Evil: His eyes appear plain black, unlike his underlings, whose eyes are red. He may not even have eyes, just holes where they should be like the Stalkers, but it's hard to tell.
- Body Horror: In addition to his general creepy anatomy, he also has what appears to be amputation scars on his chest, shackles, and mutilated legs that have been burned to vestigial stubs. But Marc Laidlaw denies that this is the result of being captured by the Combine, which is a common fan theory.
- Color-Coded for Your Convenience: His orbs all have distinct roles, and are distinguished by color and shape.
- Blue: Balls of energy that kill anything they come into contact with.
- Green: Teleports whoever it touches.
- Gold: Provides a powerful personal shield that protects him from damage.
- Energy Ball: Can launch dozens of energy balls at a time; they each deal a ton of damage, but they can be (barely) avoided with strafing because Gordon Freeman can strafe at over forty miles per hour.
- Evil Sounds Deep: Has a voice that can probably be best described with adjectives like "vast" and "bellowing."
- Fat Bastard: His torso looks a little more human-like than the other Xen aliens, making it somewhat noticeable that he looks overweight. This is likely the result of his legs being vestigial, and him floating around everywhere.
- Fetus Terrible: What he looks like.
- Final Boss: Of the first Half-Life.
- Flunky Boss: As a secondary attack, the Nihilanth can launch a green orb that either teleports you to another room or spawns some Vortigaunts or Alien controllers in his chamber. The second option isn't so bad, since he only spawns a few at a time, but him teleporting you to another room is very frustrating. In one instance, he'll teleport you to a room with a Gargantua, forcing you to have a boss fight in the middle of another boss fight.
- Foreshadowing: His telepathic messages drop quite a few hints in regards to the Combine, the G-Man, Gordon, and possibly Breen and Shephard."Their slaves... we are their slaves... we are..."
"Deceive you... he will deceive you..."
"Alone... not you alone... not you alone"
"You are man... he is not man... for you he waits... for you..."
"Done.. what have you done..." - Hypocrite: Has no problem or self awareness in enslaving the Vortigaunts, brainwashing them and ordering those very same aliens to slaughter mankind. Even if it was an act of desperation, he did the very same things the Combine does as standard practice. Despite the fact that he witnessed their atrocities.
- It's Personal: He screams Freeman's name and before that, calls him out for killing the Gonarch. This implies he may have gained a grudge for trying to stop the invasion.
- Load-Bearing Boss: Killing the Nihilanth causes him to explode, which knocks Gordon out.
- Also one in-story; his psychic powers were the only thing keeping the portals between the Combine's universes and Xen closed. When he died, the Combine were free to pour through Xen, and then to Earth.
- Large and in Charge: The largest alien ever encountered in the series in terms of pure size. Even bigger than the three-story tall tentacle monsters.
- Last of His Kind:
Word of God reveals that the Nihilanth's species was systematically wiped out by the Combine, something he himself alludes to just before Gordon enters his chamber:Nihilanth: "...The last. I am the last..." - Leaning on the Fourth Wall: Much like the G-Man and the Vortigaunts, most of his comments may be just as much about the player as they are about something in-universe, and open to many theories. For example, in the quote below, he is both the last of his kind, possibly the last thing keeping the Combine away from Earth, and the last boss.
- Meaningful Name: Word of God says "Nihilanth" is meant to imply nihilism. The -anth suffix relates to the flower-shape of his head.
- Mighty Glacier: The Nihilanth has some of the strongest attacks of any Xen alien. However, thanks to his slow, deliberate movements, the attacks take a long time to prepare, giving Gordon ample time to find cover. The Nihilanth is also a huge target, and he can't move horizontally, only capable of slowly turning around in place or moving vertically.
- Moral Myopia: He seems rather disgusted with humans resisting him, as he tells Gordon he's deceived, is enraged with the Gonarch's death, soberly implies he's been a slave and tells him he is the "last". The thing is, he started the invasion. Not even bothering to reach a peaceful alliance with humanity. He also enslaved another species and basically brainwashed them to be hostile to humanity. Said creatures are quite joyous at his death. To say that he calls humanity out for their resistance, despairing over being the last of species, nearly being made into a servant and feeling disgust at the loss of life of a creature is quite hypocritical. After all, he seems to see no problem with sending hostile forces that kill humans on masse and enslaving the Vortigaunts. He is effectively doing exactly what the Combine's MO is, which is both genocide and slavery on a planetary scale. There is also the fact that Gordon didn't even intend to land on the Gonarch's island, so he was more or less forced to fight her to procced.
- My Brain Is Big: His head takes up over half of his entire body!
- Pivotal Boss: He never moves from his point in the center of his room. Also...
- Power Floats: Nor does he touch the ground.
- Psychic Powers: The only psychic seen so far, aside from possibly the G-Man, who can affect things on a planetary scale. He was able to keep open a dimensional rift, telepathically mind control an entire species, and, judging by what happened after he died, was powerful enough to trigger disastrous portal storms all over the Earth, resulting in Xen wildlife killing off most of Earth's native fauna. Compared to that, his personal combat abilities (which are still formidable) seem rather unimpressive.
- Puzzle Boss: To actually damage him, you need to find out that he is using the crystals to regenerate his force field and destroy the crystals. After that, his protective orbs won't regenerate, and he can be killed, but it takes quite a bit of damage.
- Rank Scales with Asskicking: Just like the Combine Advisors, he leads a large army and has very powerful telekinetic powers, which include the ability to teleport himself and others, telepathy, the ability to shoot extremely powerful balls of lightning, and levitation. His commanders and possible relatives, the "Alien Controllers", also possess these abilities, but to much less powerful degrees.
- Say My Name: The very first thing he says to Gordon in person is a chilling, angry bellow: "FREEEEEEEEEEEMAAAAAAAN..."
- Shock and Awe: The Nihilanth's primary means of offense are lightning balls. If these projectiles just barely miss their target, a tendril of electricity shoots out from them and latches onto the victim to compensate.
- Strange-Syntax Speaker: His speech pattern is best describe as being similar to Yoda's speech but with making a point by repeating himself.
- Straw Nihilist: Both his name and his cryptic comments to Gordon imply that he long since crossed the Despair Event Horizon and become a nihilist.
- Telepathy: He broadcasts telepathic messages to Freeman all throughout Xen, and can also use this ability to communicate with other Xen creatures.
- Turns Red: Surprisingly, throughout the battle with him, his attacks become progressively weaker. Before his forcefield is destroyed, he's able to throw dozens of projectiles at a time. After the forcefield is destroyed, he can only muster the energy for a single projectile, taking just as long to prepare it as he would with a full set of them.
- Well-Intentioned Extremist: The Nihilanth invades earth, slaughtering dozens of innocents, and runs a bizarre slave-like society in Xen, but they do this to stop The Combine, who are ''far'' worse.
- What the Hell, Hero?: The Nihilanth is actually warning Freeman the entire game to cut it out ("Deceive you... will deceive you...", "Their slaves... we are their slaves... we are...", "The truth... you can never know... the truth...") Basically, the Nihilanth was the one thing preventing the Combine from invading Earth.
Vortigaunts
Vortigaunts
Appearances: Half-Life | Half-Life: Opposing Force | Half-Life: Blue Shift | Half-Life: Decay | Half-Life 2 | Half-Life 2: Episode One | Half-Life 2: Episode Two | Half-Life: Alyx
"We have endured these chafing bonds for eons, yet a single moment of further servitude seems intolerable!"
Voice Actor: Lou Gossett Jr. (Half-Life 2), Tony Todd (Episode Two, Alyx) (English)note
"We bear witness to the bright eternity of the Nihilanth's demise. You leap, you fall, we see you flash between the barriers."
A race of peaceful aliens linked to something called the Vortessence. They were enslaved by the Nihilanth as factory workers and militia, and were one of the most common enemies in the original Half-Life; after the fall of the Nihilanth, they were free to converse with humanity and, come the arrival of the Combine, join the Resistance.- Aliens Speaking English: Interspersed with their native language and phrases.
- All There in the Script: The "Lone Vortigaunt" in Half-Life: Alyx never gives his name, but the game files seem to suggest his name is Gary. The Final Hours of Half-Life: Alyx confirms it to be his official name.
- Alternate Company Equivalent: In the first game and its expansions (and mods), Alien Slaves were direct counterparts to the Imps from Doom, which several Half-Life developers cited as a key inspiration for the game. Red eyed, hooved, hunchbacked, brown-skinned, clawed, screeching, Cannon Fodder goombas visibly at the bottom of the enemy hierarchy, who go down after a few pistol rounds and attack by either throwing a powerful but easily avoidable projectile or clawing with their superhuman strength in melee range. They became distinct when Half-Life 2 and its expansions started giving them actual character.
- Binomium ridiculus: They are referred to with the scientific name "Xenotherium subservilia" (Subservient alien beast).
- Bizarre Taste in Food: In Half-Life 2, the "All-Knowing Vortigaunt" is roasting a Fast Headcrab on a spit, and Vortigaunt cooks can be seen preparing a Headcrab meal at Black Mesa East. This is reinforced in Alyx, where the Vortigaunt that helps the titular character can be seen cooking and eating headcrabs in his hideout. He offers one to Alyx, though she doesn't follow suit.
- Characterization Marches On: In the first Half-Life game, the Vortigaunts were little more than typical alien mooks that Gordon would plow through without any indication of being any more intelligent than the other mindless creatures that come from the Resonance Cascade. The sequel games establish that the Vortigaunts are rather philosophical, have some sense of omnisciency, and are actually peaceful beings for the most part. Several of them even help to assist Gordon and Alyx during their adventures, and are nothing but benevolent towards humanity. Justified, as it's later revealed that the Vortigaunts seen in the first game were brainwashed and enslaved by the Nihilanth to kill their enemies. The file name for them in the first game was even "alien_slave".
- Cowardly Mooks: On the harder difficulties in Half-Life, Vortigaunts wounded enough will simply stop attacking and try to run away from Gordon, though they'll still attack if cornered or if Gordon turns his back to them.
- Death Is Cheap: Apparently, via the "Vortessence":"What seems to you a sacrifice is merely, to us, an oscillation. We do not fear the interval of darkness."
- Easily Forgiven: Played with: the Vortigaunts don't seem too upset about you killing scores of them in the first game. Justified as you had no choice but to fight them and the surviving Vortigaunts see what you did as more of a Mercy Kill. On the other hand, speaking to a vortigaunt enough gets you this line:"We cannot forget those whose cords you cut. Forgiveness is not ours to bestow."
- Fate Worse than Death: The All-Knowing Vortigaunt states that Freeman did the enslaved Vortigaunts a favor by killing them. Considering the Lone Vortigaunt in Alyx was forcefully cut off from the Vortessence and the Vortigaunt Hive Mind, it's likely that the enslaved Vortigaunts from ''HL1'' suffered the same fate.
- Heel–Race Turn: Since the original Half-Life. They weren't actually evil in the first place, as they're enslaved by the Nihilanth. After Gordon frees them, the Vortigaunts aid the La Résistance against the Combine.
- Hive Mind: An entire race somehow connected on a metaphysical level by the Vortessence... whatever that is.
- Interspecies Friendship: By the time the events of Half-Life 2 roll around, the surviving humans and Vortigaunts left on Earth have become friendly with one another, and are more than willing to team up to take down the Combine at all costs.
- Lightworlder: Considering the Vortigaunts spent a good amount of time in Xen (which has lower gravity than Earth), they could count as such. Although, how much they're considered true lightworlders is left ambiguous, because they adapted to Earth's gravity very well and have Super-Strength. Not to mention that details about their actual homeworld are never revealed.
- Magic by Any Other Name: They can shoot lightning, they can charge your suit, they can heal critically-injured Alyx, and power generators. And it's all just put down to "the Vortessence"
- Medium Awareness: Ambiguously so. Some of their dialogue implies that they are either aware of the player or the G-Man."Far distant eyes look out through yours."
"Could you but see the eyes inside your own, the minds in your mind, you would see how much we share."
"How many are there in you? Whose hopes and dreams do you encompass?"
"Something secret steers us both. We shall not name it." - Mundane Utility: Several Vortigaunts in Half-Life 2 and its episodes are frequently seen using their Vortessence powers for less than fantastic purposes, such as activating generators, powering small appliances, or (in one instance) welding a weapon to an airboat. One Vortigaunt even charges the HEV suit with its powers.
- Not Always Evil: In the first game, they were typical Mooks for Gordon Freeman to mindlessly kill. It turns out, they were only fighting you because they were enslaved by the Nihilanth, and they help La Résistance in the second game and its episodes. (Sharp eyes at the time noted they were wearing control braces. That and their name in the game files was alien_slave) Whoops. The G-Man tries to make Gordon feel guilty about this later on.
- No Name Given: Vortigaunts never name themselves, with whatever names they do have being given by others, leading to notable Vortigaunt NPCs being given nicknames based off the location they're found. Amusingly enough, since Vortigaunts struggle to understand the importance of names in humans, it leads to them referring to the names of others like titles (The Eli Vance, The Freeman, The Magnusson, etc.).
- One-Man Army: You didn't think that the humans were the only ones with these, did you?
- X-8973 and R-4913, the two Vortigaunts from the PlayStation 2 exclusive expansion, Half-Life: Decay. They are noticeably more durable than standard Vortigaunts, have stronger and seemingly more developed electrokinesis, and can regenerate health by damaging enemies. Something of a downplayed example though, as they work as a team and only get to take down twenty or so soldiers in the small bonus chapter in which they appear.
- The three Vortigaunts in Episode Two who slaughter dozens of antlions, turning what used to be a tough Hold the Line moment into a glorious Curb-Stomp Battle. The one that accompanies you throughout the mines, nicknamed the Victory Mine Vortigaunt, is probably the best example.
- Reality Warper: Not to the same extent as the G-Man, but per Word Of God
, they are capable of altering reality the same way that he does at the end of Alyx. In fact, the events of Episode One are only possible because they rewind time to undo Gordon being put back in stasis at the end of Half-Life 2. - Seers: Their abilities allow them to witness the past, present and future so as long as their kind is around to share the memories with the Vortessence, a collective conscious of sorts that Vortigaunts tap into. When the lone Vortigaunt suffering from brain damage manages to convince Alyx into rescuing his imprisoned kind despite her hesitation, he jolts in surprise for a moment as if seeing something and excitedly celebrates like it had already happened, and just before that revealed that he's already witnessed Eli's death by the way events are currently playing out.
- Shock and Awe: Their primary attack is releasing bolts of lightning from their fingertips and, later on in the series, can even thrust their energy-charged hands to the ground to create a potent energy-based shockwave for a better crowd-control attack.
- Slave Mooks: Were used as enslaved foot soldiers in the first game, but then Gordon Freeman freed them from control of their alien masters.
- Slave Race: They've been enslaved by both the Nihilanth and the Universal Union long before the events of the first game. While their subservience to the latter is only briefly glimpsed in Half-Life 2, it's shown in full force during Half-Life: Alyx, where captured Vortigaunts are used to power substations that keep the Vault afloat.
- Squishy Wizard: Only when in relation to the powers of the Vortessence, given their One-Man Army feats and Super-Strength. Episode One and Episode Two demonstrate that the Vortigaunts possess immense psychic powers that rival the abilities of the G-Man, but the Combine's many Vortigaunt victims (one of whom can be found in Nova Prospekt) and Gordon's own body count during the Black Mesa Incident also shows that they're just as vulnerable to physical danger as humans are.
- Even the playable Vortigaunts in Half-Life: Decay's bonus levels are noticeably more fragile than the other player characters due to the lack of armour system that the HEV/PCV/kevlar-wearing human protagonists have, relying on speed and mobility to defeat the HECU grunts.
- Spell My Name with a "The": They always call you and Alyx "The Freeman and the Alyx Vance". It even extends to Eli, who the Lone Vortigaunt/Gary calls "The Eli Vance".
- Starfish Aliens: Downplayed. While Vortigaunts still have a humanoid shape, that's where the physical similarities between them and humans end. They have at least four eyes, three arms, lightning powers, and some sort of Hive Mind (that may or may not overlap with the very (vort)essence of the universe).
- Starfish Language: Vortigese and the related "flux-shifting" ranges from a 'normal' spoken language to telepathy to a language where two vortigaunts have to talk at the same time to properly communicate.
- Super-Strength: While it is not as pronounced as the strength of the Grunts, they still have it. The very first time you encounter one, it breaks down a 20mm thick heavy metal door with a few hits, with the door being reduced to pieces.
- Took a Level in Badass: In the first game, they were disposable mooks, slaughtered in droves by Freeman and the soldiers. By Half-Life 2, they're much more powerful combatants (individually about on par with the original's Hard mode Vortigaunts) and have gained new mystical abilities including, at one point, resurrecting someone from the dead. In Episode One they also demonstrate the ability to suppress the powers of the reality warping, time traveling G-Man himself.
- Time-Travel Tense Trouble: The Vortigaunt that helps Alyx in her titular spin-off has this as a result of a lobotomy performed on him by the Combine; Since the Vortigaunts can see into the future through others of their kind, they can know what will or or has happened. However, since he had been cut off from the Vortessence, he gets confused as to whether he's seeing the future, past, or present.
- What Is This Thing You Call "Love"?: Implied in Alyx. When Eli and Alyx say tell each other they love them before heading their separate ways, the Vortigaunt who accompanies Eli repeats it to Alyx, albeit in an awkward and stilted way, as though he has never heard the phrase or understand what it means.
- The Worf Effect: The Vortigaunts are the only creatures so far capable of opposing the G-Man on near equal footings, to the point that even the Combine (well, their token Earthly branch that is) has to rely on their energy to keep the G-Man imprisoned. This does bring up the interesting question of how absolutely bonkers the Combine must be if they could enslave the entire Nihilanth species, which in turn enslaved the Vortigaunts.
Headcrabs and Zombies
Headcrabs and Zombies
Appearances: Half-Life | Half-Life: Opposing Force | Half-Life: Blue Shift | Half-Life: Decay | Half-Life 2 | Half-Life 2: Episode One | Half-Life 2: Episode Two | Half-Life: Alyx
Clockwise from Top Right: Standard, Gonarch, Fast and Poison
Parasitic alien lifeforms. Originally from an unknown dimension far from Xen, they were eventually brought there by the portal storms. After the Resonance Cascade and the following portal storms, the headcrabs migrated and set up shop on Earth. Their most notable quality is their ability to turn humans (and possibly other creatures) into Zombies by attaching to their heads. On rare occasions they can mature into a Gonarch, a queen headcrab capable of rapidly birthing offspring.In Half-Life 2, the Combine are shown utilizing them as a biological weapon, launching them into Resistance settlements to zombify their inhabitants. They also now come in Fast and Poison varieties, though it's unknown whether these are previously unseen natural mutations or the result of biological engineering by the Combine.
- Achilles' Heel:
- Zombies, being vulnerable to all weapons but not always being worth the ammo, their usually slow movement, easy attack patterns and big center of mass makes the Gravity Gun the most ideal weapon to use on them, able to reuse large objects to instantly splatter a zombie and move onto the next. Conveniently, the Gravity Gun is acquired right before entering Ravenholm, which has plenty of furniture, reusable sawblades and explosive tanks to help you learn the ropes of the weapon.
- Headcrabs themselves go down to one whack with the crowbar, and can be swatted out the air in a single swing when they lunge to encourage this.
- Action Bomb: Zombine will sometimes decide to pull their grenade out and sprint at their enemies to explode on top of them. They usually warn of this attack ahead of time by moaning out Bouncer! or Extractor!, letting the player know they can either avoid the bomb or try to snatch/knock it out their hands to use against something else.
- And I Must Scream:
- Victims of headcrabs in 2 are more than likely still alive and conscious, even when the alien is controlling the rest of their body and actively mutilating their innards to better suit its purposes. Playing the standard Zombie audio backwards in 2, Episode One and Episode Two reveals that they're begging for help and wailing in pain when lit on fire. This was made more obvious in Alyx where Zombies don't speak backwards anymore and are more intelligible.
- Combine zombies, Zombine, are either conscious enough or are so brainwashed by their training that they actively point out that their area is infested with headcrabs, saying things like "Sector is not secure" and "Biotics in perimeter" into their radios in pained expressions.
- Art Evolution: They've had a couple major redesigns over the series, with the standard headcrab starting out in a pale yellow tone with long claws and tiny eyes on the front of its body, and their second major redesign made them fatter and sport shorter limbs with a tanned brown hide instead, while also losing the eyes on their front. By the time of Alyx, their skin is now pale and smooth, they got their longer limbs back their belly-mouth is now completely animated with chomping motions.
- Artifact Mook: In Half-Life 2 they appear to end up as such, since they (and, occasionally, their victims) are often found in abandoned areas even when there are no headcrab shells around. It's not out of the question, however, that these are remnants of the portal storms following the Black Mesa incident, just like the Antlions, Barnacles, and other alien wildlife now residing on Earth.
- Body Horror:
- For unknown reasons, headcrabs mutilate a persons body, possibly because as a parasite they are draining its "resources". Standard Zombies have their ribcages open like teeth and their organs are on display. The bloodied faces of the victims aren't much better. In the original Half-Life, it appeared some of the mutations happened as a result of the headcrab fusing with the victim, becoming a warped mass of flesh overtop the skull.
- It gets worse with elite zombies. Fast Zombies look like all of the flesh save the bare muscle is gone. The Poison Zombies are being eaten away: they have a smashed in looking "face", an exposed skull, and an exposed spinal column. Gonomes from Opposing Force have even the headcrab undergoing some substantial effects, with its front limbs withering away after having effectively become the host's new face.
- Shooting zombies reveal particle effects of yellow-green headcrab blood, showing that the zombification process changes all of the host's blood.
- Butt-Monkey: In a way they are this, even if they are pretty damn creepy. They are usually getting obliterated by the rebels, the Combine, and even the Xen Bullsquids, and the game itself actively encourages you to kill them in "creative" ways such as throwing saws, using traps, or setting them on fire. Of the four factions competing for control by the end of Half-Life 2, they are probably the weakest, with their only saving grace being their sheer numbers.
- Cat Scare: A single lowly Headcrab or its Zombie are sometimes set up to spook the player but otherwise pose a minimal threat. Poison Headcrabs are a favorite to use in particular for their unsettling shrieks and ability to wipe out an entire HP reserve for a few seconds, but are otherwise harmless when fought alone.
- At two separate points in Route Kanal, crouching into hidden crawlspaces for hidden supplies will also yield a severed Zombie torso that crawls after the player.
- After exiting Ravenholm, likely when the player is sick of fighting off Zombie and Headcrab hordes and relieved to see the sun again, a lone Poison Headcrab is hidden behind some crates at the tunnels exit as a farewell for the player.
- Creepy Long Fingers: A common symptom of being caught by a headcrab of any type has the hosts hands rot away to expose their finger bones, used as claws for slashing. Half-Life 1 zombies in particular had particularly massive finger claws that would touch the floor if they weren't always raised.
- The Determinator: Some of the zombie types count as this, as even after being cut in half, they will still crawl around using their arms trying to get at Gordon.
- Bonus points to the Zombines, who still radio in reports of the current situation even while being controlled by a headcrab.
- Elite Mooks: In the first game, there were just basic headcrabs and zombies. The later games introduce new forms.
- Opposing Force has the Gonome, a mutated version of the standard headcrab zombie. Not only does it have more health than a normal zombie, but it can throw some sort of projectile and sprint.
- Half-Life 2 introduces the fast headcrabs and poison headcrabs, as well as their accompanying zombie forms.
- Alyx adds armored headcrabs that only take damage from their underbelly, as well as the "lightning dogs"; an offshoot headcrab breed with a tail that can fling energy projectiles, spawn a smoke cloud to obscure the player's vision, and re-possess slain zombies to give them a harmful aura of electricity.
- Facial Horror: On full display with victims of the Poison and Fast Headcrab types, the formers face rotted into a Ghostly Gape and the latter being reduced mostly to a bloodied skull with some muscle still attached here and there.
- In Alyx, older Headcrab victims have their faces digested away, with their eyes and nose in particular missing, leaving emptied and bloody sockets on their melted away faces. It seems to only apply to old victims, as new hosts still have their eyes and face intact, if stretched and warped from living their Headcrab for a while.
- Face Full of Alien Wing-Wong: Which causes Barney to refer to them as "head humpers".
- Fate Worse than Death: Headcrab zombies can be heard crying out in pain, and playing their audio backwards reveals a large amount of dialogue such as "God Help Me! Help me!" or "Get it off me!" This heavily implies that headcrab victims are aware of what's happening but unfortunately there is no way to remove headcrabs without killing the victim.
- If there was ever any doubt for their victims' awareness after being overtaken, Zombies in Alyx no longer speak backwards and are audibly heard crying in pain and shouting coherent pleas for help.
- If there was ever any doubt for their victims' awareness after being overtaken, Zombies in Alyx no longer speak backwards and are audibly heard crying in pain and shouting coherent pleas for help.
- Flunky Boss: The Gonarch continually spawns baby headcrabs that attack Gordon relentlessly.
- Fragile Speedster:
- Invoked for all of the Headcrab variants, of course, who can all pounce a large distance to take a bite out of the player, but go down in a few hits to basically anything.
- Fast headcrab zombies are the fastest ones by far, and are arguably the most dangerous for this reason. However, they have no more health than a standard zombie, and so are only a big threat in large numbers and
being pretty annoying as well.
- Glass Cannon: While the Poison Headcrab is only a little more durable than the more common variants, it can temporarily reduce the player's health to 1 HP and thus, leaving the player vulnerable to other enemies.
- The Goomba: Both the zombies and the headcrabs themselves, with the former being almost a complete non-threat due to their slow speed, low health, and weak attacks, and the latter dying in one or two hits from just about anything and doing next to no damage.
- Hell Is That Noise: Headcrab noises are all horrible, whether alone or from a zombie. Special mention has to go the poison headcrabs which make three distinctive noises: a disarming chirping noise, a rattle that sounds like a rattlesnake rattle, and when they attack they let out a horrible high-pitched scream that sounds almost human.
- Kill the Host Body: In Half-Life 2 and its Episodes, killing a zombie with a bodyshot will usually cause the headcrab to let go of their head and walk freely to attack again. While it's really not all that dangerous save for letting poison headcrabs on the loose, you'd still do well to aim for the head.
- King Mook: The Gonarch is a queen headcrab.
- Lightning Bruiser:
- Puns aside, the "lightning dogs" from Half-Life: Alyx are this. Although their lightning attacks don't do a lot of damage on their own, they're fast and skittish and are capable of tanking multiple shotgun blasts before dying.
- Zombine wear full-body armor and start fights in a slow shuffle, but can quickly close the gap by enter a jogging pace to charge enemies, and they especially love to pick up the pace when they have a grenade in their hand.
- Long-Lived: Apparently the case for headcrabs who have their own zombie at least, as hosts are seen to be able to survive for fairly long times with their headcrab attached and be no worse for wear or ability, besides the number the headcrab did to them. In Alyx, some zombies are still wearing what looks like civilian clothing, implying that people caught by headcrabs before the Combine came and razed the planet over a decade ago are still alive and active when encountered in the quarantined zone.
- Mama Bear: The Gonarch is not affiliated with the Nihilanth in any way, she's just a headcrab queen trying to protect her young from (in her eyes) a violent armored alien monster invading her nest.
- Mascot Mook: They've become this due to being unique but common enemies.
- Non-Malicious Monster: Like the Antlions, despite being quite threatening and a dangerous threat to both Combine and Resistance operations, they're not really evil and only operate on a basic animal-like intelligence.
- Not-So-Harmless Villain: Due to how easy it is to kill them, it's easy to forget just how dangerous they can be. For proof just look at what they did to Ravenholm.
- Off with His Head!: Zombine, when killed with a powerful blow like a headshot or explosion, will send their headcrab flying off and reveal the Combine soldier's head to be severed by the jaw hinges. Presumably, the headcrab hung on so tightly around their helmet that blowing it off just ended up tearing half its victim's head away.
- Personal Space Invader: They have a habit of flinging themselves at people's heads.
- Punny Name: Zombine - who are zombified Combine soldiers.
- Puppeteer Parasite: They effectively replace their victims heads, controlling their every actions. There seems to be enough of their host's mind left to be horrified at their predicament.
- Super Drowning Skills: Because of their stubby legs and permanently open mouth, headcrabs don't last too long if they happen to land in water.
- Tragic Monster: Each of the zombies used to be human, and are implied to still feel real pain and possible sentience.
- Too Many Mouths: Since the head is obstructed by the Headcrab itself latching on it, the zombies will instead consume food through their stomach, which explains the gaping hole in zombie stomachs.
- White Shirt of Death: All the classic zombies in Half-Life 2 and episodes wear very bloody white shirts.
- Zerg Rush: Zombies are fond of this tactic in Ravenholm and City 17, post-collapse of the Sector 17 Overwatch.
- Zombie Apocalypse:
- Can cause this if they show up in large numbers. The Combine exploits them as a terror weapon for this exact reason, firing torpedoes loaded with headcrabs to create infestations in areas held by the rebellion, such as the town of Ravenholm.
- Shortly after the fall of City 17's defenses after the Uprising began, a population boom of Headcrabs managed to latch onto the heads of many rebels, civilians and Combine troops and end up creating a fourth faction causing major casualties in the middle of the all-out war. Even after the City was completely destroyed when the Citadel blew up, what could be hundreds of headcrab victims shambling their way from City 17 created pressure for the rebels and Combine hunting each other down in the forests. One horde in particular is fought in Episode Two, with what feels like a limitless amount of zombies being the only thing keeping the Combine at bay and on the defense with sentry cannons.
Antlions
Antlions
Appearances: Half-Life 2 | Half-Life 2: Episode One | Half-Life 2: Episode Two | Half-Life: Alyx
Clockwise from Top Right: Worker, Soldier, Guardian, Grub, Guard
Large, insect like creatures that migrated to Earth following the portal storms. They seem to operate much like many Earth insects, living in extremely large colonies with other antlions. After the events of Half-Life 2, the street war between the Combine and the Resistance has caused a breakdown of the Combine defenses, and the antlions have started pouring in to civilized areas.- Acid Attack: Antlion workers can projectile-vomit large globules of acid, which hurt Freeman as well as poisoning him. Outside of combat, workers use this for carving out the tunnels in their rocky nests.
- Alien Kudzu: Implied, as they're so ridiculously common on Earth ever since the invasion that the coast is lousy with Antlions, to the point where merely walking on the beach is enough to incur the wrath of the hive. Antlions, Leeches, Seagulls and occasionally Headcrabs are the only creatures still found living on Earth's beaches.
- Attack Animal: They can be commanded and used as expendable assault teams by anyone who has the Antlions' pheropods in their possession. Gordon Freeman uses the pheropods to his advantage during Half-Life 2, essentially gaining his own private army to let him and Alyx Vance effectively storm Nova Prospekt all on their own. The main issue, of course, is that one needs to first kill an Antlion Guard in order to get these pheropods.
- Big Creepy-Crawlies: They resemble Earth's arthropods, albeit over-sized. Even their offspring resemble beetle grubs.
- The Brute: Antlion Guards are these for the swarm as a whole, using their heft to crush enemies.
- Bullfight Boss: Antlion Guards (and the Guardian) tend to use their charge attack when at a distance, but have a lot of trouble coming to a stop and turning around afterward. Freeman can take advantage of this to lay on the hurt.
- Call a Smeerp a "Rabbit": Besides living in sand, they don't resemble real-life antlions. Their only commonality is attacking things in the sand, but for Xen Antlions, this is less of a hunting tactic and more of a hive defense mechanism.
- Cannon Fodder: Antlion soldiers. The most commonly encountered ones by far, they pretty much just charge and attempt to bite/claw whatever is threatening the colony with little regard for personal safety. They can jump pretty far and quickly maul normal humans with their teeth and claws,note but lack external weapons or any real intelligence. Good thing they're extremely numerous.
- Defeat Equals Explosion: Antlion workers explode when they die, shooting acid everywhere.
- Elite Mook: Antlion workers, which use their wings to jump around more often, have twice as much health as Antlion soldiers, and spit acid with deadly accuracy.
- Evil Versus Evil: Their presence is quite a help to the Resistance, as it gives the already overstretched Overwatch occupation force something else to shoot at. Though to be fair, they're not evil so much as animalistic. Once Gordon gets the pheromones, they're actually pretty helpful allies.
- Expy: Especially the basic soldiers look and behave a lot like the Bugs from the Starship Troopers films.
- Eyeless Face: It can be hard to tell, but they have no eyes and so rely on pheromones to tell friend from foe.
- Flipping Helpless: The Gravity Gun can be used to flip Antlion soldiers and workers upside down, causing them to helplessly flail their legs about while they try to upright themselves. While flipped, Antlions can't actually do anything to hurt you, and one shot from any other weapon kills them instantly.
- Flunky Boss: Antlion Guards are usually fought alongside regular Antlions, with the exception of the two in Nova Prospekt, since at that point the standard Antlions are temporary allies.
- Giant Mook: Antlion Guards, which can soak up bullets and grenades like a sponge and punt APCs with a headbutt.
- Insectoid Aliens: They greatly resemble giant beetles. Their grubs also resemble giant maggots.
- Made of Plasticine: Antlions are the only enemies in Half-Life 2 that can be gibbed.
- Mama Bear: Don't mess with their grubs. Seriously, don't.
- Mysterious Past: In a sense, with them having some unknown connection to the Vortigaunts (who have even domesticated some of their species to a certain extent).
- Non-Malicious Monster: Like the Headcrabs, despite being incredibly dangerous and a significant threat to both Combine and Resistance operations, they're just animals pursuing their natural lifestyle and defending their hives. More sympathetically than headcrabs, antlions care strongly for their own: as noted below, woe betide those who squash a grub in the presence of a Guardian!
- Sensory Overload: Since antlions are both blind and deaf, they rely vibrations to orient themselves. Thumpers take advantage of this by creating vibrations so strong that even the mighty myrmidonts are forced to stay away from them.
- Short Range Guy, Long Range Guy: Antlion soldiers and guards are melee combatants, while Antlion workers keep their distance and shell Freeman with their acid spit.
- Super Drowning Skills: Antlion workers and soldiers cannot swim to save their life. Tricking them into jumping in water, or shoving them in with the Gravity Gun, spells certain doom for them as they flail about for a few seconds and then just die.
- Taking You with Me: Don't get too close to an Antlion worker when it dies; its acid will splatter all over the place, which will hurt you.
- Unstoppable Rage: If you mess around with Antlion grubs, the Antlion Guardian will. Get. Pissed. The Guardian that appears in Episode Two actually leaves the nest to hunt down and kill Freeman in revenge for breaking in and killing their young.
- Zerg Rush:
- During Half-Life 2, they have a tendency of doing this — they will even push the player onto the sand, summoning more Antlions.
- During Episode Two, they do this once Gordon reaches Griggs and Sheckley's hideout. Fortunately the aforementioned rebels are quite adept at killing them, not to mention they have two turrets as backup.
Barnacles
Barnacles
Appearances: Half-Life | Half-Life: Opposing Force | Half-Life: Blue Shift | Half-Life: Decay | Half-Life 2 | Half-Life 2: Episode One | Half-Life 2: Episode Two | Half-Life: Alyx
- Achilles' Heel: Although their immobility is already their biggest drawback, the crowbar kills them in a single hit in Half-Life 1 and 2. It is downplayed however, as Barnacles are usually placed too high for the player to kill with the crowbar and even if you purposefully bring yourself up, you have the risk of getting hurt from fall damage or being subject to any other enemies nearby.
- Alien Blood: Averted in the first Half-Life, where their blood was red unlike other aliens.
- Call a Smeerp a "Rabbit": They're called barnacles but resemble absolutely nothing like them. The one trait they do share is extreme immobility but that's about it.
- Crippling Overspecialization: Their ability to bring food to themselves with a long tongue (which deals lots of damage) comes at a cost of being totally stationary throughout the majority of their lifespans. Somewhat reconstructed as there are many real life animals that are very slow moving but have a slow metabolism to compensate for this; these Barnacles are just totally immobile instead, which in real life, isn't an impossibility as real life Barnacles also do not move often.
- Extreme Omnivore: They'll eat just about any living thing, from humans to Antlions to birds. On the other hand, should they pick up something they cannot eat such as wood, they'll chew it a little, get frustrated and spit it out. They'll even remember the taste of said inedible object and will not latch onto it if they touch it.
- Glass Cannon: Despite it being killed easily with any conventional weapons, the Barnacle can mow down an NPC including the player in few seconds while chewing in the first game. While in its sequel, it will instantly kill an NPC via Neck Snap. However, the player can take 10 damage points per bite, thus giving the latter enough time to whack the said beast.
- Neck Snap: How they instantly kill non-player characters in the second game. Freeman is immune, possibly due to his HEV Suit.
- Overly-Long Tongue: Weaponized, as they wait for prey to wander into their dangling tongues and drag them up to devour them.
Alien Grunt
Alien Grunts
Appearances: Half-Life | Half-Life: Opposing Force | Half-Life: Blue Shift | Half-Life: Decay |
- Armor Is Useless: In regular Half Life their armor is actually quite powerful and deflects most attacks that hit it, but in Half Life: Source it actually does nothing, because the engine is unable to handle different materials on a single character model.
- Bee-Bee Gun: Their weapon, the Hivehand, which shoots alien "thornets", which are less like bees, and more like flying, poisonous, heat seeking armor-piercing daggers of death that can find you anywhere
- Cyborg: Their armor and weapons look like they have been surgically grafted on to their bodies, and the Grunts themselves are artificially created in a factory.
- Dumb Muscle: Averted. While their strength is mainly emphasized over their smarts, they clearly use strategy in their skirmishes. They use tactics such as firing their Hivehands to track those hiding behind cover and running between cover themselves when the opportunity sees fit.
- Elite Mooks: They're much more dangerous than Vortigaunts, the other foot soldier of Xen in the first game, due to their high health, heat seeking projectiles, and armor.
- No-Sell: Shooting the armored parts of the Grunts will simply do no damage at all if you shoot them with a pistol, shotgun, assault rifle, or even an uncharged Tau Cannonnote . Oddly enough (and good for the player), their armor is placed just about everywhere but the Grunt's torso, the most likely place it is to get shot.
- Multi-Armed and Dangerous: Continuing the Xen theme as seen in Vortigaunts and Controllers.
- This isn't all they share; like the Controllers, they also have the Vortigaunts' red eyes, vertical opening mouths, backwards jointed legs, hoofed feet, bipedal posture, two legs, and claws (well, on their third arm at least).
- More Teeth than the Osmond Family: It can be hard to tell, but their mouths consist of several razor-sharp teeth arranged vertically (think like the teeth on a zipper).
- Organic Technology: Their main weapon, the Hivehand, mentioned above, is a textbook case. This trope applies to the Grunts themselves, as they are a...
- Servant Race: Towards the end of the game, you can find a factory run by Vortigaunts, with several barrels on an assembly line. Opening these barrels will reveal Alien Grunts, with the implication being that the Grunts are a manufactured species, fitting in with the general bio-technology theme of Xen.
- Super-Strength: In various scripted scenes, they're seen doing things like prying open steel doors with their bare hands, or punching marines through metal walls.
Gargantua
Gargantua
- Ambiguous Robots: Their seemingly metallic skin and built in weapons makes one wonder. They actually share a few traits with Combine synths.
- Cyber Cyclops: Gargantuas have a large single red eye, and they seem to be biomechanical creatures.
- Cyborg: Possibly. It does look pretty mechanical. Special mention goes to its built in weapons, glowing machine-looking eye that changes colors, and armored metallic skin. Not to mention the way they explode.
- Death from Above: How one is taken out at the end of Surface Tension; Freeman calls in an air strike on it, and the HECU aircraft, not knowing who sent the signal, are happy to oblige. Cue exploding Gargantua.
- Defeat Equals Explosion: If they managed to be killed, then they scream and explode, disappearing fully.
- Interestingly enough, this is subverted if one views their full death animation, as they don't actually explode when killed but rather just flop down like a corpse.
- Kill It with Fire: They have flamethrowers built into their arms.
- Lightning Bruiser: Don't let their big size fool you into thinking they're slow as molasses because they can run just as fast as you can, or even faster. While their only ranged attack is a slow foot stomp that's easy to dodge, Gargantuas have a pair of gnarly flamethrowers that will melt your health very quickly and these guys not only take tons of hits to kill, normal bullets don't work against them, forcing you to use explosives, energy weapons, or traps. This is taken a step further in Black Mesa where Gargantuas are completely immune to your weapons, and they can only be killed by scripted events.
- Made of Iron: Bullets just bounce harmlessly off their skin. It takes a TON of explosive or electrical damage to actually put them down, more than the actual M1 Abrams tanks in the game. Even more so in the mod Black Mesa (a recreation of Half-Life 1 in HL2's engine), where there is absolutely no conventional way to kill them, even with all the explosives the player can carry; they can only be taken down with scripted sequences.
- Meaningful Name: Gargantua, as in it's an absolute behemoth.
- Mini-Boss: They serve this role whenever they appear in the original Half-Life; they're very tough, and half the time are meant to be taken down in scripted sequences to boot, but don't last as long and aren't as powerful as the actual bosses, of which there were only three (the Tentacle, the Gonarch, and the Nihilanth).
- Natural Weapon: They can open their arms to release streams of fire/plasma/something that's powerful enough to actually reduce a human to Ludicrous Gibs rather than just burn them. They're also fond of simply crushing their enemies, or shooting a weird energy beam by stomping on the ground that can seek out targets and, again, gib them.
- Puzzle Boss: Every one you meet is intended to be taken out using the environment in some way. You can kill them with weapons, but it requires almost your entire inventory of explosives to do so.
- Red Eyes, Take Warning: They sport a large red eye. The Black Mesa mod makes their eye glow brightly, giving them an even more menacing appearance than before.
- The Juggernaut: Bullets don't do a damn thing against it what with its metal carapace, and even if its still susceptible to both energy weapons and all explosives it's going to take a lot of ammunition to bring it down. It also still says a lot when the only things to one shot it are very strong discharges from a power station or a direct hit from an airstrike, both instances being very coincidental.
- Walking Tank: Notable because they actually resemble a giant version of the primary Xenian heavy infantry unit, the Alien Grunt. Both are bipedal, both have backwards jointed legs, hoofed feat, red eyes, multiple sharp teeth, and two arms ending in weird hand-less ends that open up. See◊ for◊ yourself.◊ This the only real hint we get it in-game that they're part of the Xenian military rather than just wild animals... well, that and the fact that they don't attack sentient Xenians the few times its possible to get Gargs and Vortigaunts in the same room. The same doesn't apply for Xenian wildlife.
Alien Controller
Alien Controllers
- Airborne Mook: They fly around using psychic powers, which can make them very annoying to hit.
- Cyborg: Not inherently obvious on the in-game model, but early model renders◊ show them to be immensely mechanical.
- Dying Race: According to Marc Laidlaw, they became either this or just outright extinct after the death of the Nihilanth.
- Energy Ball: Their main method of attack.
- Levitating Lotus Position: They strike this pose of the "hands closed together" variety whenever they launch their energy bolts at you.
- Made of Iron: Despite being squishy looking, Controllers can take more damage than even the fully armored HECU soldiers, and much more than the Vortigaunts. This is likely because they have a weaker, invisible version of the Nihilanth's psychic shield, as they share many other abilities with him and do not visually wear any armor.
- Mini Mook: They resemble the Nihilanth in many ways, but according to the Nihilanth himself, they're not of the same species (he regards himself as the last). They somewhat look like hybrids of Nihilanth and vortigaunt, so maybe they're an artificial crossbreed species created after his slaves and himself.
- Monster Modesty: They wear a red Loincloth, notable because unless you count the Grunts' armored groin piece, no other Xen species wears clothing, not even their master.
- Mook Lieutenant: According to Laidlaw, the Controllers are basically conduits for the Nihilanth's psychic control of the Vortigaunts, and as a result are the highest ranked "generic" aliens on Xen.
- Multi-Armed and Dangerous: Just like the Nihilanth, Vortigaunts, and Alien Grunts.
- My Brain Is Big: Their Head:Body ratio is even higher than the Nihilanth's
- Power Floats: They float around rather quickly, making them hard to hit with several weapons.
- Psychic Powers: Similar to the Nihilanth, though much less powerful.
- Shock and Awe: Via ball lightning, unlike the Vortigaunts' charged beam.
Houndeyes
Houndeyes
- Bizarre Alien Biology: They sport 3 legs and a "face" comprised of a cluster of eyes under a single giant eyelid. Their mouths are found on its belly, beneath the eyes.
- Blown Across the Room: An active hazard when fighting Houndeyes, as their attack can chuck a player a couple feet.
- Color-Coded for Your Convenience: A Houndeye's sonic-boom attack varies in damage depending on the color of the blast. Teal means it's at its weakest, while violet means its at its strongest. Damage is influenced by the presence of a pack leader and how many pack members are supporting it, as explained in this video.
- Conservation of Ninjutsu: Inverted; a Houndeye's shockwave attack strengthens when more Houndeyes are nearby and part of its pack.
- Fantastic Fauna Counterpart: They act like pack wolves despite being from another world/dimension, and even make some sounds that sound similar to dog whimpering/barking.
- Super-Scream: When a Houndeye is preparing to attack, they'll start howling very loudly while charging their sonic-boom before blasting their target.
- Taking You with Me: Unintentional on the Houndeye's part, but due to the indiscriminate nature of their sonic boom attacks they're incredibly dangerous to fight in close quarters whenever explosives are involved. If a Houndeye is howling next to an explosive crate in front of you, you'd better have a quick aim or dive out the way, because it's going to splatter both itself and whatever's near it in a few seconds.
Bullsquid
Bullsquids
- Berserk Button: Bullsquids are programmed to attack headcrabs first, no matter who is in their sight.
- Bizarre Alien Biology: They only sport two legs, have a carnivorous cephalopod mouth, are camouflaged similarly to leopards, and can spit out globs of corrosive spit at prey.
- Lightning Bruiser: Relatively quick, and are noticeably more sturdy than most of other Xen wildlife as well as having some lethal attacks to their name. Fortunately they tend to stand still or charge directly at the player, so hitting them isn't usually too hard.
- Mix-and-Match Critters: Names aside, they have traits of cephalopod, leopard-print skin and what looks like an amphibious nature.
- Noodle Incident: A Bullsquid is apparently responsible for Eli Vance's missing leg. The implication is that one ate his leg, but the exact circumstances aren't quite known.
- Tail Slap: Bullsquids possess surprisingly powerful spinning tail-smack finisher which often reduces a victim to Ludicrous Gibs.
Alien Aircraft
"Alien Aircraft"
- Ambiguous Robots: Similar to the Gargantua, it's unknown what the dividing line between their armaments and their bodies is.
- Airborne Mook: They're the only form of aerial forces seen being used by the Nihilanth's forces.
- BFG: The powerful energy weapon they have built into their bellies, which in various scripted sequences is seen doing stuff like disintegrating rather thick rock formations and reducing an Osprey to scrap in less than a second of sustained fire.
- Death from Above: Averted; they'll never attack targets on the ground.
- Final Boss: One is the final boss of Decay.
- Flying Seafood Special: Hence why they're commonly called "Manta Rays" by fans.
- Gentle Giant: When encountered on Xen, they're completely harmless, and are pretty much the only moving thing that won't attack you. On Earth, however, they act as a dropship for the Xenian forces and directly attack HECU aircraft.
- Lightning Bruiser: Can take as much damage as a tank and fly at speeds that at least exceed Mach 1, as evidenced by the shock waves they create.
- Made of Iron: You only actually fight one once, at the end of Decay. It takes as much damage as a tank to put down, though that may just be its Final Boss-ness in action.
- Natural Weapon: A laser-like weapon built into their belly that they can fire downward. It bears some resemblance to the weapon used by Combine Gunships when spawned by the console.
- Teleporters and Transporters: They appear to have a teleporter built into their bellies, allowing them to drop alien soldiers from Xen.
Tentacle
Tentacles
- Achilles' Heel: Grenades and explosive charges, though not because they can damage it. The creature can't see and relies on ground vibrations to find prey, so chucking a grenade across the room or setting up some charges to explode will fool it into aggressively attack the blast-site to no avail, and lets Gordon sneak away unharmed.
- Barrier-Busting Blow: The first introduction to the Tentacle is when its appendage smashes through a control booth to grab an unfortunate scientist who caught its attention into its maw.
- The Bus Came Back: After being absent from the series since Decay, Alyx can encounter some baby Tentacles in Half-Life: Alyx.
- Combat Tentacles: They're literally called Tentacles and they can rip Gordon up just by stabbing him with their bladed tips.
- Degraded Boss: The first Tentacles are a Beef Gate that Gordon spends some time trying to destroy and bypass, because they're directly in the way out of the rocket silo. More Tentacles are encountered on the surface and in Xen, but in much more navigable circumstances, and sometimes while missing some of their appendages.
- Eaten Alive: The fate of anything caught by the tentacles.
- Kaiju: The tentacles already tower over most enemies like a two-story building, but the long fall down into the burrow indicates it to be more or less a kaiju in size.
- Kill It with Fire: The first ever Tentacle encountered happened to have burrowed itself beneath a space rocket. Naturally, it meets its end when Gordon fires up the rocket thrusters to utterly incinerate it.
- Sinister Scythe: The Tentacles' blades are shaped like scythes, except they're bigger and more effective at killing than actual scythes.
- The Misophonic: Their entire concept. They're very sensitive to all sorts of sound and will bang their beaks aggressively to any spot where they hear a noise, including areas where Gordon can walk on. This can be used to their advantage to distract them via explosives or simply crouching and avoiding where their beaks bang.
- Too Many Mouths: The tentacles have a sucker under their beak, but at the same time they drag prey to the main body's pit, implying it has also a mouth.
Snark
Snarks / Squeak Grenades
A Snark equipped as a weapon.
The Snark, also known as the Squeak Grenade, are small, beetle-like creatures with four legs, a single green eye, and a thick, dark red, segmented shell and a tendecy to explode after attacking. Because of this they can be used as a biological weapon. It can be found in Snark Mines / Snark Nests, and will attack the player when the mines are tripped. However, the nests can be picked up and snarks can be used as weapons that can be thrown towards enemies.- Action Bomb: After a minute of frenzy they explode on their target.
- Attack Animal: In Half Life 1 and its expansion packs, Snarks are used as live grenades that home onto enemies, although they can also attack their wielder if said wielder isn't careful. Invoked by the Xen forces as in "Forget About Freeman!", they use mines filled with snarks to try and stop intruders.
- Badass Adorable: Absolutely adorable, to the point that Alyx keeps one as a pet in Half Life Alyx. Still, a group of them are dangerous and Snarks are primarily used in Half Life as live homing grenades.
- Berserk Button: To pretty much any biological entity in game, including you. Reconstructed because there are many animals in real life that act aggressively to any animal around their surroundings, mainly because they're territorial and want to prevent any competitors from trampling on their land.
- The Bus Came Back: After being absent from the series since Decay, Alyx has a pet Snark that she can feed in Half-Life: Alyx.
- Equippable Ally: Double Subverted, as they can help kill enemies that the player wants to kill, but if they find no other enemies (or the enemies that aren't allowed to be attacked by them), they will instead attack the player. They will even attack you just after they killed a few foes.
Ichthyosaur
The Ichthyosaur
- Achilles' Heel: The crossbow. Not only does it do a lot of damage but it can be fired underwater and can uniquely stun the Ichthyosaur temporarily for a few seconds. The bolts do have drop underwater, however, if you're not firing forward. It is justified as the crossbow, along with doing other tasks, is implied to have been built to combat these monsters in mind.
- Aquatic Mook: You only see these guys in water environments, like a dam reservoir, and a flooded lab.
- Call a Smeerp a "Rabbit": They are named after a real (if extinct) marine reptile, but don't really have anything in common other than also being an aquatic predator, and aren't even from Earth.
- Fiendish Fish: Absolutely. They're even more scary as their attack sound often breaks when they charge at you by repeating multiple times.
- The Cameo: It's not a normal enemy in Half-Life 2, and is only seen when it nearly attacks Gordon in a lake during the Teleporter Accident near the beginning of the game.
- Non-Indicative Name: It's named after the extinct marine reptile group but looks like a mix of a tiger, a Hydralisk, and a piranha.
Leeches
"Leeches"
- "I, eh, hope you like leeches."— The Fisherman (Half-Life 2: Lost Coast)
- Alien Kudzu: They're dangerously common on Earth, and they've rendered most sea life extinct or endangered by eating them all during their stay.
- Art Evolution: In the original game, they looked like a hybrid between a leech and a fish. Meanwhile in the sequel, they look more like eels by comparison.
- Border Patrol: Having overwhelmed the ocean life, Leeches are practically the only things encountered in beach water anymore in 2. They'll swarm and kill Gordon if he's too deep in the water.
- Death of a Thousand Cuts: They're not particularly damaging, but they tend to show up in great enough numbers that they're a threat when Gordon needs to swim underwater in the submerged parts of Black Mesa. In 2, they're encountered when Gordon tries to swim too far into the ocean, and will eventually bite him to death if he doesn't get out.
- Demoted to Extra: In the original game, they used to be actual NPCs. But in 2, they're just a damaging entity to prevent the player from going too far into the water or bypassing the path.
- From Nobody to Nightmare: They went to the weakest enemy in their debut to an actual threat to the ocean life in the sequel.
- The Goomba: In 1, where they used to be far weaker than the Headcrabs and died from a single crowbar whack.
Revivers
A subspecies of headcrabs that are able to generate electricity. Alyx encounters them as she makes her way through the Northern Star hotel.
- Attack Its Weak Point: As a Revived Zombie, Alyx has to shoot the Reviver several times as it moves around the zombie's body in order to coax it out.
- Alien Blood: Unlike most Xen lifeforms, which bleed yellow, this creature has fluorescent blue blood.
- Blinded by the Light: When approached, a Reviver will flash a bright light followed by a thick, black smoke in order to escape.
- Call a Smeerp a "Rabbit": Both Alyx and Russell refer to them as "lightning dogs".
- Deadly Lunge: Like their headcrab brethren, they will lunge at Alyx should they spot her.
- Dual Boss: Alyx has to fight two of them near the end of the Northern Star chapter.
- Flunky Boss: The dual Revivers are accompanied by several headcrab zombies and will quickly overtake their bodies once Alyx kills them.
- Lightning Can Do Anything: They use their trademark electrical powers to puppeteer corpses, creating an incredibly deadly zombie in the process.
- Living Battery: Their hearts are so overcharged tthat they can be used as substitute Combine batteries.
- Mini-Boss: Serve as one during the Northern Star chapter, with Alyx having to fight them in maze-like areas.
- Our Zombies Are Different: Unlike zombies, which are (barely) living beings created via headcrab parasitization, Reviver zombies are completely dead corpses that are reanimated via electrical impulses generated by the Reviver. Thus, they can't be gunned down directly like headcrab zombies; Alyx needs to force the Reviver out of hiding by shooting where in the body it's hiding.
- Recurring Boss: Four Revivers are fought during the Northern Star chapter.
- Reviving Enemy: Are able to resurrect dead headcrab zombies by entering the cavity on their chest, which also grants the newly Revived Zombie its electrical powers.
- Shock and Awe: Can naturally generate electricity and defend themselves by firing an electric orb at their enemy. Revived Zombies are also able to send out bolts of electricity.
- Turns Red: Inverted. After taking enough damage, it will start limping around whilst making whimpering sounds.
- Underground Monkey: A variant of headcrabs encountered by Alyx while traversing through the Northern Star hotel.
- Unique Enemy: Only appear in the Northern Star chapter.
Jeff
"Jeff"
- Arc Villain: Of Chapter 7 in Alyx, which is aptly named after him. He's the primary threat Alyx must avoid as she navigates the vodka distillery.
- Body Horror: His split human head revealing two sets of teeth, which is now shaped like a Venus Fly Trap, is only the tip of the iceberg for Jeff's condition, to say nothing of the massive, spore spewing boils on the rest of his body.
- Fluffy the Terrible: One of the most horrific monsters in the game and he's simply known as Jeff. Justified, as he was once a normal human hazmat worker before being turned into what he is now and he's solely named by his co-worker Larry.
- Handicapped Badass: Jeff will absolutely rip you to shreds if he can find you, but his blindness makes evading him relatively easy... as long as you are careful around bottles and spore clouds, of which there are several in the vodka distillery he inhabits.
- Healing Factor: If you pay close attention, this is why shooting Jeff doesn't work: he will simply heal whatever damage is dealt to him.
- Immune to Bullets: Jeff is so heavily mutated that nothing Alyx can carry will hurt him. The trash compactor, on the other hand, will do just fine.
- Invincible Minor Minion: Jeff is flat out immune to any of the weapons that Alyx can carry, making stealth a priority when around him. After you trap him in the trash compactor, though, you can kill him by just turning the machine on.
- Ludicrous Gibs: Reduces several headcrabs to this. He himself will become an example if you activate the trash compactor while he's in it.
- Our Zombies Are Different: Rather than being the series standard definition of a zombie with their headcrab, Jeff seems to be a person who was overwhelmed and mutated by Xen spores.
- Pun: "Near-Jeff Experience", the achievement for staying right next to him for 10 seconds.
- Sense-Impaired Monster: His skull is split open like a Venus flytrap, rendering him blind, so he navigates by sound, requiring Alyx to quietly sneak around. This is more difficult than it sounds, both because empty glass bottles litter the halls, alerting Jeff if she bumps into them and because Jeff emits clouds of spores which will cause Alyx to cough if she walks through them without a gas mask or covering her mouth, again alerting Jeff. However, Alyx can also distract Jeff by Throwing the Distraction, to lead him away from her momentarily.
- Single Specimen Species: For whatever reason, nothing remotely like him has been seen at any prior point in the franchise.
- Super-Senses: His hearing is so precise that he'll zero in on the location of the noise to investigate and attack whatever made it. This can also be used against him, as throwing objects across the room as a distraction keeps him busy for a little while.
- Suspiciously Similar Substitute: As a blind enemy that is not damaged by any conventional weaponry, requires stealth or misdirection to avoid, and is only killed when activating a certain device, Jeff is essentially the Alyx equivalent of the Tentacles from the first game.
- Tragic Monster: He was once a completely normal human before his horrific and painful mutation.
- Was Once a Man: Was once a normal human Combine hazmat worker, before he was heavily mutated into the blind monstrosity Alyx faces in Chapter 7.
- Zombie Puke Attack: His primary form of attack is to start throwing up a torrent of caustic blood from his maw.
