A net of twinkling lights floats out of the blackness, and one can almost hear a buzzing sound as it comes closer, drawn by vitality.

Void Swarm (CR 4; XP 1,200)
Diminutive outsider (swarm)
Init +3; Senses darkvision 60 ft., blindsense 120 ft.; Perception +11
AC 21, touch 21, flat-footed 18
(+3 Dex, +4 natural, +4 size)
hp 52 (7d10+14)
Fort +9, Ref +7, Will +5
Defensive Abilities swarm traits; Immune void immunities, weapon damage SR 15
Weakness swarm traits, nickel (if applicable)
Speed fly 60 ft. (good)
Melee swarm (2d8 plus dissolution and vampiric healing)
Space 10 ft.; Reach 5 ft.
Special Attacks dissolution (W- DC 13), distraction (F-DC 15)
Str 1, Dex 17, Con 14, Int —, Wis 16, Cha 13
Base Atk +7; CMB —; CMD
Skills Fly +13, Perception +11, Stealth +15
Environment vacuum
Organization solitary, pair, or alignment (3-6 swarms)
Treasure none
Special Abilities
Dissolution (Ex) The attacks of a void swarm erode the target’s presence on the Material Plane, eventually making them incorporeal and without substance. The recipient must make a DC 13 Will save or lose 1 point of base AC (making their base AC 9) and 1 point of Constitution. Lost Constitution can be recovered normally, but base AC loss must be treated with a restoration spell for each point, as if it were a permanent negative energy level loss. The save DC is Wisdom-based.

In the dark outer spaces of the universe, strange creatures move and live, mate and consume, largely unknown to the terrestrial races below. Void beasts live here, alien in thought and behavior, not caring for the warmth and comfort of atmosphere or even a surface to rest upon. Mirroring the surface world, there are creatures large and small in the void, and even the tiny members of the insect world have a parallel in the cold dark of the vacuum, forming the lowest level of the food chain, but dangerous nonetheless. These are the void swarms.
Void swarms consist of thousands of heavily carapaced, insect-like creatures that individually resemble nothing so much as a four-headed mosquito, about the size and shape of a caltrop. Even outside the void, they are completely silent,depending upon their generated light to attract prey. Motivated by energy patterns, void swarms migrate through hard vacuum in wave-like patterns, reproducing when they are able to catch other corporeal beings and absorb their reality-substance. They are fed upon by some of their fellow void-beings, and by certain terrestrial creatures that know of their existence, such as skywhales and outer dragons.

Void swarms migrate between the gravity fields of Shankhil’s Chair and Vaar’s Eye, the two moons of Porphyra, moving with the extraterrestrial tides. Their migration patterns affect the movements of the pods of skywhales in The Reversed Lands of eastern Tuthon, and the work of the intrepid skywhalers of Bugtown. In rare instances a magical researcher enamored of the void will summon a void swarm to the surface, but they need to be maintained in a vacuum environment for all but the shortest periods of time.