Thunderjaw

Size
 Origin
 Class
 Function
 Override
 Weakness
 Strength
 Weakpoints

The **Thunderjaw** is a category of machine in Horizon Zero Dawn. A large Combat Class machine, the Thunderjaw was designed and developed by the AI HEPHAESTUS due to its hostility toward humans for machine hunting. Its size, power, and array of highly damaging attacks make it the most feared machine among the tribes, so much so that it has attained an almost legendary status.

## History

Unlike the Zero Dawn terraforming machines, which were designed and controlled by Zero Dawn’s governing AI GAIA, the Thunderjaw was designed by HEPHAESTUS, which had previously manufactured the machines under GAIA’s direction. When GAIA self-destructed, HEPHAESTUS gained absolute control over machine design and management as well as manufacture. Hostile toward humans for their predations on the terraforming machines for parts and resources, HEPHAESTUS made the machines hostile to humans, a phenomenon the tribes call the Derangement. It then began producing Thunderjaws and other combat machines as the next logical step in protection and deterrence against hunters.

The Carja hunter Ahsis, a Hawk of the Hunters Lodge, is the first known hunter to have killed a Thunderjaw. After the huge machine destroyed the Carja freehold of Morning Light, Ahsis tracked, found and engaged it. His weapons proving ineffective, he prevailed by removing and wielding its Disc Launchers against it. Unarguably the largest and most powerful machine ever successfully hunted in the Lodge’s history up to that time, the kill elevated him to the rank of Sunhawk of the Lodge.

His achievement was eventually topped by the successful hunt of another Thunderjaw. Known as Redmaw, this Thunderjaw had for years slaughtered every hunter who had attempted to kill it, earning it legendary status among Carja hunters. Eventually, Redmaw was killed by Hawk Talanah Khane Padish and her Thrush Aloy, now a highly experienced and skilled hunter. This kill came after Ahsis' failed attempt to have Talanah murdered to prevent her supplantation of him as Sunhawk, and his own demise when he himself tried to kill Redmaw.

## Appearance

The Thunderjaw is a huge bipedal machine whose chassis resembles the body of a theropod dinosaur, particularly the Tyrannosaurus Rex: large and powerful hind legs, a long body, a sizable head, and a heavy tail to maintain balance. Unlike a Rex, however, Thunderjaws do not have arms or front legs. Its mouth consists of a three-mandible jaw. Twin optical sensor arrays are located on its head, in the same position where a theropod’s eyes were. Twin pulse energy cannons are mounted on its lower mandibles, and another energy beam weapon is mounted in its mouth. A radar scanner is mounted on its back, at the base of its neck. An array of Blaze canisters is on its back, heavily protected by armour plating. Under its belly is an array of similarly protected Chillwater canisters. Mounted on its hip are its most well-known weapons: Disc Launchers. On its lower back are three long, antenna-like structures. The tip of its tail is armed with a pair of scythe-like fins, which it uses along with the crushing weight of its tail for melee attacks. On its head, protected by armour, is a component known as a data nexus. Located laterally at the base of its thorax is its "heart", which is most likely its CPU. Heavy armour plating covers the entire chassis in overlapping segments, giving superb protection against all but the highest tear damage weapons. This armour also protects the machine from elemental damage.

## Behaviour

Like most large machines, Thunderjaws are generally solitary. The only known instance of Thunderjaws congregating is at a site in a valley in the eastern region of the Sundom, where two Thunderjaws guard a herd of Lancehorns. While most of the seen Thunderjaws are scattered throughout the Sundom, a Daemonic unit exists in The Cut, and one is also found in The Longroam.

When undisturbed, Thunderjaws mill about their respective sites, their footfalls heavy enough to shake the ground, knocking over trees and smashing boulders in their way.

## Abilities

The Thunderjaw’s huge size, power, capacity to sustain damage and array of weapons make it one of the most formidable machines. It employs a range of powerful melee and ranged attacks. Additionally, its radar scanner allows quick detection of hunters hiding in tall grass. Unlike the radar of a Scrapper, which cannot detect still humans, the Thunderjaw’s radar can detect humans regardless of their motion. Thunderjaws have no elemental weaknesses, and are resistant to Shock.

A Thunderjaw’s major tactical weaknesses are its heart and data nexus; ranged weapon strikes on either cause significant damage once they are exposed via the removal of the armor covering them. Corresponding elemental ammunition strikes on the any of the Thunderjaw’s Chillwater or Blaze canisters cause a corresponding elemental explosion once they are similarly exposed, and can respectively induce a Burn or Freeze state. Pneumatic concussion ammunition such as Tearblast Arrows remove the Thunderjaw’s mounted weapons such as its mandibular cannons and Disc Launchers, and also remove its radar scanner.