Radscorpion

“Radiation has mutated the common Emperor Scorpion into the deadly Radscorpion, one of the Wasteland's fiercest predators. Beware its claws and poisoned stinger.” — Fallout 4 loading screen hint
Radscorpions are arachnids mutated from the emperor scorpion, found in the Commonwealth and Nuka-World in 2287.
Background Radscorpions are large, mutated scorpions commonly found in and around abandoned structures. They originated from the North American Emperor scorpion, which were prolific in many pet stores at the time of the Great War. They have since mutated to become much larger, faster and more venomous than ever before.
Biology Radscorpions sport highly venomous stingers, the ability to burrow underground in seconds, powerful claws and durable exoskeletons. Unlike Mojave or Capital Wasteland variants, the Commonwealth does not feature radscorpions that occupy a similar size category as giant radscorpions.
Radscorpions have either migrated to the Commonwealth from the southwestern United States or mutated independently from emperor scorpions kept as pets before the War in a similar manner to ones located in different areas of the continent.
Gameplay attributes Radscorpions are fast runners, extremely aggressive, extraordinarily well armored and will use their powerful claws and poisoned tails to attack enemies quickly and relentlessly; capable of dealing a large amount of physical and poison damage in only a few hits. With their ability to burrow underground and traverse large distances seemingly instantaneously, retreating from an encounter is often impossible. Their only weak spot is their relatively small face. Deathskull radscorpions are easily one of the most dangerous creatures one can encounter while exploring the Commonwealth, completely capable of killing the player character in even the highest grades of power armor.
Due to their claw and poisonous sting attacks as well as their great maneuverability, radscorpions are powerful melee fighters that should be dealt with preferably from a distance, or with specialized equipment if a direct confrontation is necessary. If attacked from afar, they will immediately burrow and emerge close to the player character, often in melee range, provided the ground type can be navigated through by them, so it is possible to avoid being caught unprepared by standing on rocks, or metallic/wooden surfaces before attacking. Weapons with armor-piercing mods as well as the legendary modifier "Penetrating" can help to improve the damage output against their armor reinforced exoskeletons.
Radscorpions are mostly found within the Glowing Sea. They can be found on occasions in other areas of the Commonwealth as well. Radscorpions can be pacified through the Wasteland Whisperer perk.
Very rarely, an encountered radscorpion will be non-hostile to the player character and will go about their business as if the player character wasn't there. It will still attack other enemies on sight, such as raiders and super mutants. However, it will still attack the player character if they remain in close proximity for too long.
Variants
Radscorpion
Radscorpion hunter
Glowing radscorpion
Albino radscorpion
Radscorpion stalker
Radscorpion predator
Deathskull radscorpion

SPECIAL ABILITIES
IMMUNE TO RADIATION: The radscorpion reduces all Radiation damage suffered to 0 and cannot suffer any damage or effects from radiation.
IMMUNE TO POISON: The radscorpion reduces all Poison damage suffered to 0 and cannot suffer any damage or effects from poison.
BIG: The radscorpion is bigger than most characters. The creature receives an additional +1 health point per Level, but its Defense is reduced by 1, to a minimum of 1. Further, it only suffers a Critical Hit if an attack inflicts 7+ damage (after damage resistance) in a single hit, rather than the normal 5+.
BURROW: A radscorpion can tunnel under the ground to strike at attackers. Burrowing into the ground takes a major action, and while burrowing the radscorpion is not visible and cannot be targeted by attacks. It burrows two zones as a major action, moving underneath existing zones. It takes only a minor action to emerge from the ground after burrowing. A radscorpion cannot burrow through stone, metal, or wood.
WEAK SPOT: If an attacker chooses to target the radscorpion’s head, it ignores the creature’s DR. This does not apply against hits which hit the head due to random chance.
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