Reviver

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Reviver
General information
Type	Headcrab variation
Personal information
Attack(s)	Ranged electric attack, revival of dead zombies.
Game information
Entity	npc_headcrab_runner
Designer(s)	Naru Omori Christine Phelan (animations)

 

"There was like a... dog-looking... lightning thing."

― Alyx Vance

The Reviver, also called "lightning dog" by Alyx Vance, is a Headcrab variation previously unknown before the Combine invasion. It is only encountered in the chapter The Northern Star throughout the eponymous hotel.

Overview

Resembling a scorpion, the Reviver has a flattened blue body with loose skin that hangs between its limbs, a mouth lined with razor-edged teeth, and a long tail that terminates in three fins. A pulsing blue dot pattern glows through its skin on the top and underside of its body. The spherical organ at the end of its tail functions as its eye, the creature aiming its appendage towards what its facing while the eyeball darts around to scan the surroundings. On its own, it has the ability of shooting an electric ball which deals a small amount of damage and disables the indicators on the Gravity Gloves. Per its name, the Reviver can also enter the chest cavity of a dead zombie to reanimate the corpse, creating a Revived Zombie. The presence of a Reviver causes interference in Alyx's radio communications with Russell.

Upon death, the Reviver expels its heart which functions similarly to a Combine Battery, even being able to substitute in place of one.

Behavior and skills

Revivers are very skittish in nature. They prefer to wait and ambush prey, firing electrical balls from a distance to catch them unaware. When approached or hurt, they'll release a smokey electrical cloud to confuse their foe, and then either run away or pounce on their attacker. They're much more aggressive when inside a Revived Zombie. They'll lumber toward their attacker, trying to hurt them with the lightning they produce. They'll also produce long-range shocks that travel in straight lines across the floor. This change in behavior implies a somewhat symbiotic relationship with Headcrab Zombies, specifically a commensalistic one, as the Reviver does not lead to the death of Headcrab Zombie but nevertheless benefits from their death and the ability to repossess the host body.

Revivers appear to be territorial even to other members of their own species. Two can be seen growling at each other when Alyx approaches the top of the Northern Star. This is why rarely more than one is encountered at a time in the hotel. However, these two appear to put their differences aside when a more dangerous creature arrives in their domain, in this case, Alyx Vance.

After being critically injured and near death, Revivers will stop attacking and limp along the floor slowly while whimpering.

Behind the Scenes

The Reviver enemy was introduced after Valve observed that their playstesters enjoyed searching environments in VR more than they had in traditional games. In addition to rewarding players for their exploration in search of ammunition and resin, the developers wanted to utilize this exploration aspect in fighting an enemy as well. They first prototyped a Fast Headcrab variant called the Runner (which would ultimately remain as the Reviver's internal entity name). This variant used modified behavior in which it would run away and hide from the player after attacking. Valve found that playtesters enjoyed looking for a small, hidden enemy that they knew was hiding somewhere within a dense environment as well as shooting at a fast moving enemy that was able to evade gunfire by running behind everyday objects like tables and chairs. Playtesters also voiced their satisfaction in being able to be the aggressor in combat for once as the rest of the game made them feel like they were always on the defensive.

While this initial feedback was positive, the developers soon learned there was an issue in actually encouraging players to hunt for the Runner. After a few encounters, players realized they didn't need to hunt the creature as they could simply wait for it to run away once and then leave the area, avoiding the need for battle. Valve experimented with methods that would make the Runner more dangerous if not found, setting up a time pressure situation where players had to act quickly to deal with it or end up facing a worse situation. They eventually landed on a prototype where the Runner could revive a fallen Zombie, an enemy that was more dangerous than a Runner or Zombie individually. After this change, the Runner was renamed internally to the Reviver. In the end, they still felt they didn't create enough of a foolproof reason for players to need to search for hidden Revivers, so they created the Reviver's heart which acted as a key that required players to collect it.

Visually, the Reviver was initially prototyped using a blue-tinted Headcrab with rudimentary electrical effects. Once this prototyping proved successful, they created the creature's original purpose-built model, but while the developers saw that players were able to successfully identify the new Reviver, it wasn't necessarily viewed as threatening. The first animations for the Reviver were originally seen as "cute" by playtesters, refusing to kill it to proceed and some even trying to pet it. This led to a redesign of its animations to be more unsettling and menacing and introducing more aggressive behavior, adding a jump attack if players got too close.

Gallery

Pre-release

• 

  Concept art of the Reviver.

• 

  Ditto.

• 

  Concept art of the Reviver attaching itself to a leg.

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  Concept art of a Reviver dying.

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  Concept art of Xen flora resembling the Reviver's electrical attack.

• 

  The game's unused Fast Headcrab model, part of the Reviver's initial prototyping.

Retail

• 

  The Reviver's heart.

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  Close up view of the Reviver, front.

• 

  Ditto, side.

• 

  Ditto, mouth.

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  A Reviver's heart placed in the battery unit to activate the elevator.

List of appearances

• Half-Life: Alyx