Mosquito Swarm, Bloodhaze

A high-pitched whine issues forth from the haze of this surging crimson cloud. Within, thousands of tiny forms whir in agitation, each a tiny insect with a needle-like proboscis.

Bloodhaze Mosquito Swarm CR 6

XP 2,400
N Fine vermin (swarm)
Init +2; Senses darkvision 120 ft., scent; Perception +9


AC 20, touch 20, flat-footed 18 (+2 Dex, +8 size)
hp 71 (13d8+13)
Fort +9, Ref +6, Will +5
Defensive Abilities swarm traits; Immune weapon damage
Weaknesses swarm traits


Speed 5 ft., fly 30 ft. (average)
Melee swarm (1 Con damage and sleeping sickness)
Space 10 ft.; Reach 0 ft.
Special Attacks cling, Con damage, distraction (DC 17), disease


Str 1, Dex 15, Con 12, Int —, Wis 13, Cha 2
Base Atk +9; CMB —; CMD
Skills Fly +10, Perception +9; Racial Modifiers +8 Perception


Cling (Ex)

If a creature leaves a bloodhaze mosquito swarm’s square, the swarm takes 1d6 points of damage as dozens of insects tenaciously cling to the victim. A creature with bloodhaze mosquitoes clinging to it takes 1 point of Constitution damage at the end of its turn for the next 1d4 rounds. As a full-round action, the creature can remove the mosquitoes with a DC 18 Reflex save or by immersing itself in water. High winds or any amount of damage from an area-affecting effect destroys all clinging mosquitoes. The save DC is Dexterity-based. Once a group of clinging mosquitoes has dealt 4 points of Constitution damage, the mosquitoes detach and disperse to digest their meal.

Disease (Ex)

Bloodhaze mosquitoes are bearers of a terrifying and deadly disease common to the jungle, known to most locals as sleeping sickness.

Swarm (sleeping sickness)—injury; save Fort DC 17; onset 1d2 days; frequency 1 day; effect 1d4 Wisdom damage and target is fatigued, cure 2 consecutive saves or arsenic.


Environment warm forests and swamps
Organization solitary, pair, pestilence (3–6 swarms), or plague (7–12 swarms)
Treasure none

Thousands of species of insects make their home within the jungle but few elicit as much dread as the voracious bloodhaze mosquito. Migratory in nature, these ravenous insects amass in great numbers, forming swarms capable of feasting on the blood of humanoids and beasts alike. Perhaps worse, the crimson parasites carry a debilitating disease known for sapping the vitality of its victims. Because of this potent mix of teeming esurience and virulent pestilence, bloodhaze mosquitoes panic almost any community they threaten. Legends describe crimson clouds decimating entire populations on their flight from breeding pool to jungle interior. Only high winds, drought, and torrential rain consistently keep them at bay. Thankfully, the swarms also wax and wane with fluctuations in local prey populations. In combination with the mosquitoes’ relatively short lifespan, competition for food helps keep their numbers under marginal control.

A typical bloodhaze swarm contains more than 10,000 flying mosquitoes. Individually, each mosquito is smaller than a child’s fingernail, yet together they form a terrifying assault. Their iridescent wings can refract light, creating a shimmering effect as they move in unison. This effect proves disconcerting to most animals, which wisely flee such clouds, their panic often alerting other jungle inhabitants to the swarm’s presence.


Bloodhaze mosquitoes always sate themselves on the blood of other animals, using their darkvision and ability to detect pheromones to track prey. They typically lie in wait near water sources where they can both breed and feed on animals that come to drink. Warm-blooded creatures draw their attention more quickly than amphibians or reptiles, though even lizards, snakes, and frogs become food sources during leaner times.

Not only does blood provide sustenance to bloodhaze mosquitoes, but the females actually require it to reach egg-laying maturity. Females must also have water in which to lay their eggs, though even a sewage-filled mud puddle will suffice. A single female mosquito can lay up to 100 eggs, which hatch into larvae after 2 days. Many of these eggs suffer the predation of fish and other aquatic scavengers during this time of vulnerability. The surviving eggs hatch, releasing larvae that molt and shed their skins while feeding on organic matter and microorganisms in the water. Then they enter a pupal stage, conserving energy as they undergo a final transformation before finally emerging as fully grown adults. The entire hatching and growth process takes less than a single week.

After reaching maturity, bloodhaze mosquitoes swiftly take to the air, naturally drawn to one another through their pheromones and banding together in swarms strong enough to challenge any animal for territorial supremacy. The life of a typical bloodhaze mosquito spans only 3 months. They spend that time ravenously feeding in their swarms, consuming enough blood that their females can continue laying eggs. The mosquitoes possess no maternal or protective instincts, however, quickly abandoning their progeny before dying out to be replaced by them.

Habitat & Society

Bloodhaze mosquitoes live in tropical wetlands, only venturing farther away when hunting becomes scarce or high winds carry them into other regions. Unintelligent predators, the mosquitoes give off pheromones to maintain their swarm’s cohesion. Specific scent markers for distress, mating, and food rule most of their behavior. Powerful, false odors or thick and pungent smoke can sometimes mask or disrupt this communication, as can immersion in water, leading to traditions among many native peoples of coating themselves in sulphurous mud or burning reeking torches during the height of the mosquitoes’ feeding seasons.

Although bloodhaze mosquitoes don’t feed on other insects, they do prove highly territorial. While swarming, a group of the mosquitoes will attack and kill any other insects they encounter. Such ferocity can wipe out whole hives or nests of insectile jungle inhabitants, potentially having farther-reaching ramifications for other creatures speedy or canny enough to escape the swarms. In more dramatic instances, swarms might fell massive jungle insects or the populations of whole areas, leaving trails of crunching insectile corpses to mark their path.

Section 15: Copyright Notice

Pathfinder Adventure Path #38: Racing to Ruin. © 2010, Paizo Publishing, LLC; Author: Tim Hitchcock.

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