Geckos can be found living across the entire Mojave Wasteland, although different species of gecko tend to live in different areas. There are three types of gecko in the Mojave: the normal gecko, the golden gecko, and the fire gecko. Another variety, the green gecko, is found in Zion Canyon in the Fallout: New Vegasadd-on, Honest Hearts.
Geckos in general are reptilian in appearance and tend to have a pair of fins behind their head. Their eyes are an orange tint, and their body colors differ greatly based on the gecko type. Geckos also all have five fingers and five toes. Geckos can be heard gruffly breathing, squeaking and cooing from time to time.
Gameplay attributes
Geckos are generally found in small packs. They charge at opponents with their mouths open and attack rapidly, by biting and with swipes from their clawed hands. Some types can breathe fire or spit poison, and so may also attack from a distance.
Their hides can be tanned, and used to craft several types of armor which offer greater defense than regular variants.
Geckos, green geckos, and golden geckos are affected by the Animal Friend perk. Fire geckos are not.
Variants
Gecko
Geckos often appear in packs. They will charge at the player with their mouths open, and attack by biting and with swipes from their clawed hands. Geckos can be found mostly in the areas surrounding Goodsprings, and along I-15 towards Primm and the Mojave Outpost. This is the least dangerous species of gecko found in the Mojave.
Gecko hunters look identical to normal geckos, but have greater health. They are very fast, and will attempt to rush and overwhelm their prey. They may appear in place of normal geckos in certain areas when the player is at higher levels.
Standard geckos which have yet to mature fully. They are smaller and less damaging than adult specimens, but share similar behavior and may appear with them in packs.
These immature geckos are smaller and weaker than adult gecko hunters, but attack in the same way. Although appearing as hostiles, they often ignore the player unless provoked.
A type of gecko with brilliant golden scales. They can be found around irradiated areas like Crescent Canyon east and west, Vault 34, and Cottonwood Crater. Golden geckos have been affected by high levels of radiation. In addition to causing regular damage, their bites will increase the player's radiation level.
These geckos may appear alongside golden geckos, and attack in the same way. Their bites are similarly irradiated, in addition to causing regular damage.
Fire geckos have mottled purple and red hides, and prominent spikes on their backs. In addition to their bite and claw attacks, they have the ability to breathe fire. They can mainly be found in and around mountainous areas and caves, such as the Lucky Jim mine and Nopah cave.
These immature geckos are smaller and weaker than adults, but attack in the same way and share the ability to breathe fire. They may be encountered in groups with full-grown fire geckos.
The legendary fire gecko is one of several legendary creatures. It is roughly twice the size of a normal fire gecko, and its powerful and fast attacks make it a potentially dangerous opponent in close combat. It can be found in Fire Root cavern.
Green geckos are native to and only found in Zion Canyon. When attacking from a distance they can spit several far-reaching but slow-moving globs of poisonous saliva. Once in contact with an enemy they will attack like other types of gecko, by biting and clawing. Green geckos are often found near waterways and bridges in Zion Canyon.
Another type of giant creature native to Zion National Park, these geckos are larger than a human and have almost the same destructive power as the legendary fire gecko.
Another type of fire gecko exists, but was cut from the final product. Its name is Gojira. Simply called "gecko" when spawned, Gojira is its editor ID. It's identical to the fire gecko, but about triple the size and has a whopping 8,000 hit points. Gojira is the Japanese name of Godzilla.
Before the release of Honest Hearts, the green geckos were mistakenly referred to as "Greek geckos" in press material. This was corrected before the release.
Bugs
PC Geckos may not always be hostile to the Courier, even if the player doesn't possess the Animal Friend perk. However, getting too close or trying to speak to one may turn it hostile.
Xbox 360 Green geckos inhabiting Zion may not be hostile to the Courier, and approaching, or attempting to talk to them will not change their disposition, if you happen to shoot one of these geckos, simply put away your weapon and it will return to being friendly, just like a normal non-player character.
Xbox 360 In the Mojave Desert, several young gecko hunters may be found superimposed upon one another, but not moving from the spot except to flail their arms and roar loudly. They cannot be damaged with guns, and when attacked and killed with a melee weapon, the game freezes and must be reset.