Radscorpion (Fallout: New Vegas)

Radscorpions are mutated arachnids found in the Mojave Wasteland in 2281.

Background
Radscorpions are mutated, via radiation and exposure to the Forced Evolutionary Virus, from the North American Emperor scorpion, which were prolific in many pet stores at the time of the Great War.

Contrary to many expectations, their venom grew more potent when they mutated rather than becoming diluted. Though considered nocturnal and sensitive to light, radscorpions can be found active during the daytime in the areas they inhabit. Samples of their venom can be used to make antivenom. Apart from their size, they appear visually identical to normal scorpions, with mottled, dark blueish-gray carapaces.

Biology
Radscorpions are very large, about the size of a bighorner calf. They have a thick carapace covering their entire body with no definitive weak spot. Common places to find radscorpions are scorpion gulch, the scorpion burrow, the scorpion valley near Goodsprings Cemetery and the Yangtze Memorial. The area around Nipton Road reststop and Mesquite Mountains camp site is also inhabited by a large number of radscorpions. Unlike Capital Wasteland or Commonwealth radscorpions, Mojave radscorpions are not seen physically burrowing or leaving temporarily, but nonetheless do burrow as evidenced by the scorpion burrow.

Gameplay attributes
As radscorpions almost always move in groups of two to five, they can be very dangerous to low-level players. Also, the addition of Damage Threshold makes them harder to kill for an unprepared Courier. They tend to charge their intended targets directly and will use their powerful claws and poisoned tails for quick and relentless attacks.

Radscorpions take normal damage when shot in the torso, stinger, or claws, and reduced damage when shot in the legs. Unlike other creatures, radscorpions lack a "weak point" that can be targeted for extra damage (they have no "head," for example), which makes V.A.T.S. combat and firearms somewhat less effective against them. Additionally, all radscorpions are armored to some extent, making them even more difficult to kill.

Their claws are less-armored than the rest of the carapace; successfully crippling these will stun the radscorpion. Using the Guns skill, the creatures are vulnerable to armor-piercing weaponry.

Radscorpion
These are the most common variety of radscorpion. These poisonous predators seem to possess different speeds, some taking their time and others bolting at top speed. Their size ranges from that of a large dog to that of small livestock.

Small radscorpion
The smaller and less common variant of radscorpion, these creatures are likely juveniles or a smaller strain of radscorpion, as they are encountered both in the company of larger varieties as well as by themselves.

Giant radscorpion
A larger and much more dangerous variant of radscorpion that is faster, as well as rarer than the usual radscorpion. It does a lot more damage and has a higher Damage Threshold (on par with that of a sentry bot), making them particularly difficult to kill for low level or otherwise poorly equipped players.

Giant radscorpions can be found anywhere that radscorpions will gather or sometimes can be found alone. The player can encounter them very, very early on, since some of them are just outside Goodsprings and Goodsprings Cemetery.

Radscorpion queen
An exceedingly rare and special kind of radscorpion, the queen is the strongest and largest variant of radscorpion; in fact, she is larger than a Corvega. Only two are known to exist in the Mojave Wasteland:
 * One can be found in the scorpion burrow south of the Nipton Road pit stop and just east of Crescent Canyon west. The queen will be located in a large cavern with a group of other radscorpions.
 * Another queen can be found inside the Searchlight fire station, along with two regular radscorpions, accessed during the side quest Wheel of Fortune when the Courier is given the key to the fire station.

Appearances
Radscorpions appear in Fallout: New Vegas.

Behind the scenes
Regarding the tough Damage Threshold of radscorpions in Fallout: New Vegas, Joshua Sawyer said that radscorpions were made more of a threat because they look larger and scarier in a 3D engine than they did in Fallout and Fallout 2's isometric view.

Bugs

 * When viewed from a distance, the radscorpion(s) frequently slide vertically across uneven terrain (interfering with V.A.T.S. aiming). On the PC version, they can also possibly sink into the ground making it near impossible to kill them. If the Courier is unable to kill the sunken radscorpion, it remains as a red tick indicating an enemy on the radar, making it also impossible to leave the area by fast travel.
 * In the case that a radscorpion has fallen underneath the ground and the Courier's companions have weapons, the follower will attempt to attack the enemy until they either run out of ammunition or the radscorpion is killed by a general area of effect weapon, such as a grenade.