Dog

"The first model was about yea high. I've been adding to him ever since."

- Alyx Vance

Dog (written as DØg on his body) is Alyx Vance's "pet" robot. Alyx's father Eli built Dog to protect his daughter when she was young. Dog was originally a relatively small, 1 meter (three foot) high robot. As Alyx grew older, she began upgrading the robot by adding additional parts, and it now towers 2.5 meters (eight feet) high.

Half-Life 2


Gordon Freeman is first introduced to Dog in the Black Mesa East scrap yard. As part of a tutorial on operation of the Gravity Gun, Alyx arranges a game of "fetch" between Gordon and Dog, using an inert Combine Rollermine as the ball, until they are interrupted by a Combine assault on the Resistance facility. After heading back inside, Dog opens for Gordon the door to an unused tunnel leading towards Ravenholm, to aid his escape after he gets separated from Alyx. While Gordon enters the tunnel, Dog stays behind to help Alyx and the others defend the lab.

Gordon meets Dog again after he and Alyx teleport from Nova Prospekt to Kleiner's Lab at the end of the chapter Entanglement. The company splits again when Gordon and Dog set off to find Barney Calhoun, Alyx deciding to stay with Dr. Kleiner who refuses to leave without his pet Headcrab Lamarr. As the chapter Anticitizen One begins, Dog is quick to leave Gordon behind and charge at a nearby group of Combine troops outside the lab, tossing a ruined car at them and even fighting off an APC. He then forces open a Combine Barricade gate for Gordon, allowing him to proceed. However Dog goes berserk immediately after and jumps on a Combine Dropship whilst trying to attack it, departing into the unknown. It is worth noting that this whole scene – unlike other sequences where supporting characters fight alongside Gordon – is entirely scripted, and as such requires no involvement from the player at all.

Dog eventually manages to find Barney, and Gordon meets both of them in the square toward the end of the chapter "Follow Freeman!", in a scene where Dog, in the heat of the battle, knocks over a column topped with the large statue of a horse. As Barney reports to the player, Dog is probably aware of the fact that Alyx is already in the Citadel, and so tries to reunite with her, being completely uncontrollable by others. The last time Dog is seen in Half-Life 2 is when he once again opens a passage for Gordon, this time allowing him to proceed to the Citadel's foot, by lifting a heavy section of Combine Smart Barrier, uncovering an ancient sewer tunnel.

Half-Life 2: Episode One


Episode One opens with Gordon lying in the darkness under a pile of rubble. The sound of Alyx and Dog searching for him leaks through, and after lifting up a large slab of rock, Dog's head and eye appear through a hole. He seems elated, and quickly lifts Gordon out of the rubble.

After Gordon's recovery, Dog helps Alyx contact her father, using his metal body as an antenna by twisting his hand to get a better signal. After much deliberation, Alyx and Gordon decide to enter the Citadel, however they are blocked by a large ravine. Dog runs off in search of something, and soon throws over a large empty car. Testing the distance by throwing a rock over the ravine, he lets Alyx know that her and Gordon are to climb into the car, allowing him to throw them over. Eventually Alyx concedes, telling Dog to go back to Eli after he has thrown them. Gordon and Alyx both get into the vehicle, before Dog picks it up and throws it across the dividing ravine. Dog is not seen again for the rest of the game.

Half-Life 2: Episode Two


In Episode Two, Dog appears late in the game in the Outlands, when Gordon and Alyx have nearly reached White Forest. When the duo is forced to stop their car because of a gate, a Strider that was lying on the ground wakes up. Fortunately, Dog appears quickly and takes down the Strider in an epic battle, with little regard for his own well-being. After narrowly avoiding being crushed multiple times, he manages to tear off the casing of the Strider's control mechanism and subsequently shuts it down by removing its "brain".

Afterward, Dog challenges Gordon to beat him to the base in his car. If the player is able to beat Dog, Alyx will mock Dog by saying "Better luck next time, slow poke." However, if Dog wins, he will dance around triumphantly. Dog is then left outside to help MIRT patrol the area while Gordon and Alyx continue on to meet Eli and Kleiner.

Towards the end of the game, after the closure of the Superportal, Dog appears once again. He greets Alyx but is distracted by something in the distance, and goes running off much to Alyx's dismay. Whilst Dog is gone, Eli, Gordon, and Alyx go into the hangar to get to the helicopter, but are ambushed by Combine Advisors who kill Eli, inserting their appendage through the back of his neck, breaking his spinal column. Before the Advisors manage to repeat the horrific process on Gordon and Alyx, Dog shows up in the nick of time, narrowly avoiding the death of Alyx. He manages to injure one Advisor considerably, jumping onto its back and smashing it to the ground, whilst the other flees from his attacks relatively unscathed. As Alyx cradles her dead father, Dog leans over, watching in confusion and sorrow.

Personality and skills
Dog, much like a real dog, is very friendly, loyal, and has an intelligent and excitable personality. Similarly to Barney Calhoun, Dog provides much comic relief throughout the games, with his quirks and many strange and odd decisions, even dancing when he is looked at for a period of time. Dog makes friendly and playful noises such as beeps and whines, much like a real dog, especially when he is around Alyx. When provoked, he can become very dangerous to enemies, using his immense strength and weight to smash enemies to the ground or tear them apart. This makes him a pivotal force in any battle, as he can be seen destroying Striders with ease and lifting heavy objects from the ground, only to throw them into an enemy moments later. His behavior changes when around Alyx, as he becomes friendly and cautious, but still alert for any imminent danger. His protective nature makes him an excellent bodyguard, and it is understandable why Eli built him for protecting Alyx as a child.

Dog's body is constructed largely of scrap metal, hydraulics, and wires. He has what appears to be a scrapped City Scanner for a head, though with only three flaps while normally Scanners have four. He is quadrupedal but walks on his knuckles. His appearance is very unlike a dog's, and his movement is more akin to primates, mostly gorillas. His body language is hard to convey effectively, due to his large size and weight. One of his main forms of emotive outlet is his eye, which has an aperture used in much the same way as the human eye to show feelings by opening and closing, but often more prolifically. His Scanner flaps also move according to his mood.



Alyx treats dog much like a pet dog, calling him "boy" most often and using similar body language and voice as when talking to a real dog. She pats her upper thighs when calling him at Black Mesa East, and tells him to "fetch" when Gordon throws the Rollermine. Their relationship is also much like that of a dog and its master: they have a mutual trust and friendship, which has grown over the years so that Alyx now trusts Dog's opinions and hunches, as crazy as they may sometimes appear. She also has come to accept his sometimes erratic behavior, when he runs off without warning only to appear again moments later. Their relationship differs from the traditional dog and master relationship in the sense that Dog is considerably more intelligent than most real dogs, and is also much larger and more powerful than any human. However, these differences rarely come between them and their friendship seems very deep, so much so that Alyx shows many signs of affection for Dog. He also seems to have something of a sixth sense, being able to determine where Alyx is, no matter the situation. When Alyx is inside the Citadel, he is eager to get in there and rescue her.

Dog has a Zero Point Energy device, much like the Gravity Gun, built into one hand, to pick up and throw things. He has an amazing strength, and proves extremely useful through the course of the story, as he can throw large objects (such as vehicles) at enemies or make way to areas which are otherwise inaccessible to Gordon. Dog appears to be completely invulnerable to any damage; he never takes apparent damage from any source including weapons, fire, or explosions (though this is not necessarily true, as seen below).

Behind the scenes



 * Dog does not have any combat AI, and all in-game scenes with Dog fighting are scripted. If a spawned Dog is approached by anything threatening, even a common Headcrab, he will flee. If no enemies are present, he will find a nearby small object and throw it at the player, as if playing "fetch".


 * Dog's character, even though important to the story, also plays a recognizable role for the game. His battle sequences are often humorously exaggerated, where the player can see him throw large objects great distances to wipe out entire squads of Combine soldiers, or furiously attack disoriented and panicking groups of enemies without caring for consequences nor taking any noticeable damage. Whether it is crushing a handful of soldiers or taking a Dropship head-on, Dog seems to care little for himself.


 * As mentioned in the Half-Life 2: Episode One commentary, players' feedback towards Dog where very positive, hence Valve made him the first thing to be seen at the start of the game.


 * Dog was one of the few Half-Life 2 concepts that went from the first sketch straight into the game with relatively few changes to the design. Designers were inspired by classic movie robots, as Dog is a near cousin to Robbie from Forbidden Planet.


 * Early texture sheets from the playable Half-Life 2 Beta show that Dog was to feature other colors, such as aqua blue, maroon, pink or green. His head was also to be made out of a scrapped Combot, the direct predecessor to the City Scanner.

Trivia

 * Although Dog is seemingly invulnerable to damage, he simply has a huge amount of health to make sure he does not die (as opposed to using very fast regeneration of health, as Alyx does). It is possible for him to die, but this can only be observed if the player spawns him using the console in a combat situation that he would not normally be involved in.


 * The aggressive roars that Dog makes when provoked are very similar to the same noises that Striders make.

List of appearances

 * Half-Life 2
 * Half-Life 2: Deathmatch
 * Half-Life 2: Raising the Bar
 * Half-Life 2: Episode One
 * Half-Life 2: Episode Two