Bloodbug

“Is this mosquito the product of FEV or radiation?” — Curie
Bloodbugs are a species of mutated, ectoparasitic mosquitoes found in the Commonwealth in 2287.
Background The mosquitoes that inhabited the swamps of Massachusetts were mutated since the Great War and have become a capable predator in the Commonwealth. Around the size of a dog, bloodbugs attack by stabbing their knife-like proboscis into soft tissue. Although they feed upon the blood of their victims, they will also often spray this blood back into their prey's eyes to distort their vision.
The bog-standard of bloodbugs, these mutated insects attack in swarms, piercing their prey with a needle-like proboscis and feeding on their blood.
Biology Bloodbugs appear to be roughly two feet in length from the head to the tip of the abdomen. Bloodbugs possess muddy brown coloration which allows them to camouflage effectively into the environment of the Commonwealth. Like their pre-War ancestors, bloodbugs possess six long double-jointed limbs, one pair of finely-veined wings and a long, pointed proboscis that extends from between two compound eyes.
The proboscis is the bloodbug's primary means of assault, sinking it into prey almost like a syringe and inflicting minor-to-intermediate radiation poisoning on the victim. The proboscis can be collected by the Sole Survivor upon the bloodbug's death.
Gameplay attributes Bloodbugs latch onto their prey in an attempt to drink their blood. The insect then becomes engorged with the victim's blood and can spit the contaminated blood back at its target for a large amount of radiation damage, which suggests that radiation is transmitted from the mutant to the victim. While these mutated mosquitoes can punch their proboscis through any kind of regular armor, it's not powerful enough to penetrate power armor. Should they find themselves faced with such heavily armored prey, their range of available attacks becomes limited to largely ineffectual stings and their acid spit, should the target be out of melee range.
Bloodbugs are often encountered feeding on deceased brahmin. Coming across the exsanguinated, gray-skinned husk of a dead brahmin whose body is covered in oversized stings is a significant indicator of knowing there are bloodbugs nearby. Bloodbugs near certain parts of the coast are occasionally seen feeding on the corpses of sea creatures.
Bloodbugs, like bloatflies and radscorpions, have a propensity for swarming tactics. Once they are alerted to their victim's presence, they will spread out, surround their prey and attack from multiple directions. This, coupled with their erratic evasive movement while under fire, their good camouflage and their slender silhouette, makes it difficult to keep track of and kill them all before at least some of them get into melee range. However, should the majority of the swarm be destroyed before it reaches its prey, the survivors will often retreat. Usually, they will regroup and attack again, but sometimes they will flee for good without returning.
Another habit bloodbugs share with bloatflies and especially radroaches is their clinging to trees and structures, as well as walls or the ceiling while indoors and unaware of an enemy's presence. This can result in a nasty surprise when the player character enters a seemingly empty room or subway station and suddenly finds themselves in the middle of an entire bloodbug swarm. Companions will usually notice the bugs and remark upon something not being right or enemies being nearby, although they won't open fire until the creatures make the first move.
If the Sole Survivor damages the bloodbug's blood sac, it will lose its spit ability, but the bloodbug can still suck the victim's blood. If done multiple times, the bloodbug's sac will be restored and it will regain its spit attack.
Some bloodbugs near-dead brahmin can be found with their blood sac already full of the brahmin's blood. The bloodbug's enlarged blood sac can be targeted more accurately due to its size.
Variants
Bloodbug hatchling
Bloodbug
Red widow bloodbug
Infected bloodbug
Glowing bloodbug
Vampiric bloodbug

SPECIAL ABILITIES ƒ FLYING: Bloodbugs can move freely through the air. They ignore most ground-level obstacles and difficult terrain effects, and they can move through “empty” zones above the battlefield if desired. It must spend at least one minor action each turn moving, and if it is knocked prone it falls to the ground, suffering 3 DC Stun physical damage, +2 DC for each zone above ground level it was before it fell. ƒ LITTLE: Bloodbugs are smaller than most characters. The creature’s normal HP decreases to Body + 1⁄2 level (rounded up), but its Defense increases by 1. Further, it is slain by any hit which inflicts an Injury. ƒ IMMUNE TO RADIATION: The bloodbug reduces all Radiation damage suffered to 0 and cannot suffer any damage or effects from radiation.
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