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Template Grafts | Universal Monster Rules

The Swarm

Source Alien Archive pg. 110
Originally an insectile race called the kucharn, the Swarm is now a single-minded collective with a desire to consume all things and absorb their best qualities into itself. The Swarm moves from planet to planet in tremendous organic hive-ships, reducing each so-called “feeder world” to a barren husk incapable of supporting life, and occasionally altering its own DNA in the process to take on qualities from that world’s species. Once it has consumed everything of use on a planet, the Swarm moves on, not bothering to hold territory.

Ironically, one of the most violent races in the galaxy also birthed one of the most peaceful, as a mutation within a sub-hive gave life to the shirrens, who broke away to form a new species. The Swarm is notorious not just because of the invasion that finally ended hostilities between the Pact Worlds and the Veskarium, but also thanks to the warnings of shirrens, who understand the Swarm’s might and its hunger as no other race can.

While individual components of the Swarm have some form of intelligence—or at least a set of complex programmed behaviors that resembles intellect—they cannot generally be reasoned with in any fashion. Swarm components rarely communicate with other creatures, as they see every alien entity as either a food source or a threat. The Swarm’s morale is unbreakable, and while individual components might retreat for tactical reasons, fear is utterly unknown to the Swarm and its components.

The Swarm rarely wields manufactured weapons, instead integrating biotechnology grown or grafted onto component creatures. Because of its constant genetic upgrading and experimentation, the Swarm encompasses components with a wide variety of shapes, sizes, and capabilities, from the mighty dreadlancers to the microscopic, bloodstream-infesting toxicytes.

Aliens in "The Swarm" Family

Swarm Corrovox3
Swarm Dredger (Troop)5
Swarm Mindreaper7
Swarm Thresher Lord10

The Swarm, Swarm Thresher Lord

Source Alien Archive pg. 110

Swarm Thresher Lord CR 10

XP 9,600
CE Large monstrous humanoid
Init +5; Senses darkvision 60 ft., blindsense (vibration) 30 ft.; Perception +19


HP 165
EAC 23; KAC 25
Fort +14; Ref +14; Will +11
Defensive Abilities swarm mind; Immunities acid, fear effects


Speed 30 ft., climb 20 ft., fly 20 ft. (Ex, average)
Melee arm blade +23 (2d10+18 S; critical bleed 1d8)
Space 10 ft.; Reach 10 ft.
Offensive Abilities blade storm


STR +8; DEX +5; CON +3; INT -2; WIS +1; CHA -3
Skills Acrobatics +19, Athletics +19 (+27 when climbing), Stealth +24
Languages Shirren; telepathy 100 ft.


Environment any
Organization solitary or pair

Special Abilities

Arm Blade (Ex) A thresher lord has massive blades grafted onto its forearms, replacing its normal hands. A thresher lord can’t wield any other weapons, but neither can it be disarmed.

Blade Storm (Ex) When making a full attack entirely with melee weapons, a thresher lord takes a –3 penalty to each attack roll instead of the normal –4 penalty. In addition, a thresher lord can make up to three melee attacks instead of two attacks when making a full attack. If it does so, it takes a –5 penalty to these attacks.

Swarm Mind (Ex) Members of the Swarm are bound together into a singular hive mind by a blend of exuded pheromones, imperceptible movements of antennae and limbs, electrostatic fields, and telepathic communication. All Swarm creatures within 30 feet of each other are in constant communication; if one is aware of a threat, all are. (Such awareness can spread along a “chain” of Swarm creatures under appropriate circumstances, potentially alerting distant Swarm creatures.) In addition, once per round when within 30 feet of another Swarm creature, a Swarm creature can roll twice and take the better result on a saving throw against a mind-affecting effect.


The two Swarm components listed here are some of the most common aspects of the Swarm’s varied evolutions.

Corrovoxes are Swarm shock troops. They act as advance scouts and worldseekers for the Swarm, and moving vast hordes across potential feeder worlds. Like many Swarm creatures, corrovoxes have latent telepathic ability and are capable of psychically ravaging a foe’s mind. Thresher lords descend on their foes on insectile wings and, as their name implies, quickly cut prey down with the massive razor-sharp blades that grow from their arms. When the carnage is complete, other components of the Swarm arrive to feast upon the bloody remains.