Swarm · 1 hex · SM +0 Spider Swarm (Monsters on Automatic; answers SRD 3.5)
An egg sac breaks and the ceiling comes down in pieces, and the pieces are moving. Individually the spiders are harmless. In these numbers they get inside armor, inside sleeves and inside the neck of a cloak, and there is nowhere to hit that does any good.
Attributes
ST3
DX13
IQ2
HT10
HP3
Will8
Per9
FP10
Basic Speed5.75
Basic Move5
Dodge8
DR0
Melee attacks
| Usage | Level | Damage | Reach |
|---|---|---|---|
| Swarming BitesSwarming Bites: 1d-4 impaling, Reach C. No attack roll and no defense. Roll HT against the combined venom of several hundred bites or take fever and a shaking hand for the rest of the day. | no roll | 1d-4 impaling | C |
Traits (11)
- Bestial
- Cannot Speak
- Clinging
- Cold-Blooded
- Extra Legs (Eight Legs)
- Fangs
- Injury Tolerance (Diffuse)
- Night Vision 5
- No Fine Manipulators
- Restricted Diet (Carnivore)
- Vibration Sense (Air)
Notes
- Racial cost: -19 points of traits plus 0 points of skills.
- Body weight: 4.5 lb.
- Movement: ground Move 5 (primary).
Encounter rating
CER7
Offense16
Protection-9
Threat tierminor
Appearing1
Wandering4
Tags
- monsters-on-automatic
- ai-generated
- doa-authored
- srd-3-5
- swarm
- animal
- vermin
- underground
- ambusher
- venomous
GCS v5 downloads
Where this one came from
- Source record
- Spider Swarm [Monsters on Automatic, SRD coverage: swarms]
- Source system
- doa_fixture / doa_authored
- Released under
- cc_by_4_0
- Conversion
- 0.1.0-srd-independent-build
- Review status
- approved
- Credit
- Monster statistics, ratings and description prose by Monsters on Automatic; AI-generated first draft, project-reviewed, released under CC BY 4.0.
- Description
- Written by Dungeons on Automatic, released under cc_by_4_0
- Independently authored GURPS build. The SRD supplies the creature identity this record answers to and nothing else: no SRD statistics, wording or presentation is reproduced, and no third-party GURPS conversion was used as an input.
- Answers the SRD heading(s): Spider Swarm (SRD 3.5).
- Racial template: -19 points across 16 traits, plus 0 racial skill(s) worth 0 points.
- Every trait is drawn from the project's controlled GURPS vocabulary in scripts/srd/trait-library.mjs, which carries the page reference and published cost for each entry.
- sourceSystem is recorded as doa_fixture because that is the package contract's value for project-authored material; the SRD headings this record answers are in provenance.coversSourceIdentities.
- Ratings are recomputed through the consumer CER path on every build, so a mechanics change cannot leave a stale rating behind.
- Typical Stats, damage and ratings are derived from the racial template rather than authored beside it, so the sheet and the stat block cannot disagree.
- GCS ancestry draft: gcs/spider-swarm.gct
- The published Move is the primary medium's cruising Move; sprint figures are stated in the movement note and not folded into it.
- Treasure and grappling are not authored for this record and ship as explicit nulls, which reads as known absent rather than forgotten; `lair` carries a short habitat note instead, because where a creature dens is an encounter fact rather than a loot one.
- Body mass is the figure the build was scaled from and the one fact that makes it checkable; see the gurps-animal-sanity-check skill for the bands.
- One hex of swarm, which is where the Size Modifier comes from.
- Clinging matters here: this swarm arrives from above, and the ceiling is where it was waiting.
Copyright 2026 Monsters on Automatic. GURPS-compatible monster statistics, ratings and prose authored for this package as an AI-generated first draft under project review. No SRD text, and no third-party GURPS conversion, is reproduced. Portrait and tokens are AI-generated original art. Sources and credits.