The supporter's tactics have said this since it was written: "It is a flyer, and a flyer with a hole in a wing is a quadruped: disable either wing and it is on the ground for the rest of the scene, which is the fight the agents can actually win." Playing a full combat against it showed the sentence was decoration. `flightLost` was computed, printed on the NPC sheet as GROUNDED, and read by nothing. Both wings disabled cost 20% off PHYSICAL rolls, and Brawl is a MELEE category, so woundPenaltyFrom returned 0 and a grounded supporter attacked at exactly the 75% and exactly the 1d6+1+2d6 it had in the air. In the played fight it was grounded from round five and went on to kill one agent, knock out a second and leave a third dying. Losing a wing now changes the animal. A plan declares what it becomes — winged says `grounded: "quadruped"` — and hitLocationRoll drops the creature onto that plan the moment a wing is disabled or destroyed. The wings leave its hit chart and the six ranged faces they covered go back to the body: vital hits rise from 3 faces in 20 to 5. Every other wound moves across on the R-94 remap with its severity intact. The wing's own damage is deliberately dropped rather than carried, and cleared in its own update so the remap never sees it. A ruined wing must not arrive as a ruined foreleg — the creature is not lamed, it is earthbound, and the injury has already been paid out as the change of shape. check-anatomy gains a fifth property: a declared landing must exist, must have no wings of its own, must not itself be a flyer, must have room for every wound the flyer was carrying without two collapsing onto one location, and must not heal a disabled location on the way down. Three induced failures confirm it fires; the third — landing somewhere with too few locations — passed at first because I had not stated the capacity property, and the guard was sharpened until it caught it. Measured, and reported honestly: this does NOT deliver the fight the tactics text promises. Over 4,000 simulated fights the win rate moves 12.7% -> 12.1% on borough ground and 85.8% -> 86.3% off it, because grounding only happens in 9% of fights there and arrives late. What actually decides this encounter is ARGENT AND GULES: 11.4% win on borough ground against 85.4% off it. The wing rule is now real and mechanical, but the creature's advice still points the GM at the wrong lever. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
THE CUSTODIANS
A Basic Roleplaying game of crossings, as a Foundry VTT system.
A drab British government agency deals with crossings. Reality keeps a record of what belongs where, and it can be made to get it wrong. Agents are civil servants: they carry warrant cards and cordon tape, they file in triplicate, and the thing that makes them dangerous is that they know how the record works.
The tone is bureaucratic horror. Most cases close with an arrangement rather than a fight, and the supernatural is a filing error somebody committed on purpose.
Installing
In Foundry: Game Systems → Install System → Manifest URL
https://gitea.timevans.uk/slaguru666/RingBRP/raw/branch/main/system.json
Or by hand: clone this repository into your Foundry data directory as
Data/systems/ringbrp, then restart Foundry.
git clone https://gitea.timevans.uk/slaguru666/RingBRP.git ringbrp
Requires Foundry v13+ (verified against v14.364). No modules are required. Dice So Nice works if you have it, using your own dice — the system ships no dice skins and does not touch anybody's dice settings.
Deploying to a remote Foundry server
The built compendia in packs/ are committed on purpose, so a remote server needs
nothing but the files:
cd /path/to/foundrydata/Data/systems
git clone https://gitea.timevans.uk/slaguru666/RingBRP.git ringbrp
# restart Foundry
node_modules/ is not committed. You only need it if you intend to rebuild the
packs or regenerate art on that machine:
npm install # pulls classic-level, used to write the LevelDB packs
npm run build # rebuilds packs/ from tools/content.mjs
npm run check # the eight guards; the build refuses to run if they fail
To update a deployed server: git pull and restart Foundry. If the pull touches
packs/, Foundry must be stopped first — LevelDB will not tolerate its files
changing underneath a running server.
What is in the box
| Postings | 25, each with a key characteristic, trained skills, talents and its own kit |
| Trades | 10 ordinary jobs the department recruits from, plus induction |
| Catalogue | 236 items — 123 gear, 62 weapons, 32 armour, 19 vehicles |
| Skills / talents | 62 skills, 19 talents |
| Bestiary | 47 statblocks across folklore, horror and the far side |
| Eras | modern, antique, future, anomalous — the agency is old and never abolishes anything |
| Icons | 292, all generated from tools/icons.mjs; no external art |
| Starter scenario | BLACK PLATFORM, a six-player action starter, importable as a single Adventure |
| Compendia | pregens, NPCs, skills, weapons, armour, gear, vehicles, powers, tables, rules, the starter |
| Rules journal | 13 pages, generated from rules.mjs so the book cannot drift from the code |
The rules, in brief
d100 roll-under, banding into critical / special / success / failure / fumble. 96–99 always fail, 00 always fumbles, and every skill has a 1% floor.
Reaction Lanes replace Strike Rank. Initiative is
3 × max(⌈DEX/3⌉, ⌈readiness/10⌉) less carried load, plus a d6, re-rolled every
round — including the first, so the opening round is ordered like every other.
Coherence runs 10 → 0 and measures how well-filed an agent is in reality. It bands into Anchored / Loose / Adrift / Unmoored / Displaced, and spending it is how the supernatural works.
The Quiet Arts are deliberate misfilings, not spells. They cost Coherence, and they only ever arrive from a crossing that goes wrong.
Defences are graded. A defence stops a blow of its own quality or worse outright; against something better it only reduces it by as many steps as it was outclassed by. Only a critical stops a critical.
Access is a record. There is no hacking skill and nothing to break into — see below.
A weapon's fire mode is a decision. Slow weapons shoot better and then make you work; fast ones offer a second shot at the cost of both; rapid ones fire bursts; beams can be held on the target for damage instead of hits. A weapon that cannot fire a burst cannot be made to.
Sights and lamps apply themselves. A sight is graded by range band — a telescopic sight is a penalty inside ten metres — and a carried lamp buys the dark back to dim, never to daylight, and tells everyone where you are. Neither is a thing the player selects: both are facts about what is in the pack.
Borrowed Authority — the access subsystem
Deliberately not cyberpunk. Nobody jacks into anything.
What an agent has is a named credential belonging to somebody real, with a scope of things that person could plausibly do, a Trust that erodes as it is used, and red flags describing how the real owner behaves.
- Inside its scope there is no roll. A facilities contractor opening a plant room is not intrusion, it is Tuesday. It costs 1 Trust and it works.
- One tier beyond is a stretch — roll, at −20 for each red flag you break. The system is not testing whether you are clever. It is testing whether you are behaving like the person whose name is on the record.
- Two tiers beyond is impossible at any skill. No percentage on any sheet gets a contractor issuing accounts.
- A fumble burns the credential, and somebody real is going to be asked about it.
A credential is assembled, not found: up to three dossier items, each a separate scene using a different skill, at most one of them at a keyboard. Items make the credential better, never the roll easier.
AI is a posture on the target rather than an opponent — a gatekeeper raises what counts as routine, an analyst writes a new red flag every time you stretch, an asset stands in for a dossier item.
And you may spend Coherence to widen a scope, because reality can be made to remember that the person always held that duty. It works. It always works. Push a credential past what its Trust will carry and your file and theirs converge one step, and nothing in this game spends anything to converge them back.
Repository layout
ringbrp.mjs the system: sheets, engine, hooks (~5,500 lines)
rules.mjs THE SINGLE AUTHORITY for every rule formula
system.json Foundry manifest
template.json data model for every Actor and Item type
templates/ Handlebars sheets
styles/ one stylesheet
lang/en.json all user-facing text
icons/ fonts/ art/ generated art
packs/ built LevelDB compendia (committed — see Deploying)
tools/
content.mjs the catalogue: skills, weapons, armour, gear, vehicles, NPCs
build-packs.mjs builds packs/ — runs the eight guards first and refuses on failure
make-icons.mjs draws all 231 icons
rules-text.mjs generates the rules journal FROM rules.mjs
mission.mjs the case generator
mission-tables.mjs its content tables
check-rules.mjs guard: no rule may be defined twice
check-kits.mjs guard: every posting's kit must exist and be usable
check-lang.mjs guard: no localisation key may be both a value and a branch
check-lethality.mjs guard: no creature may quietly change what it does to a party
docs/REVIEW_LOG.md the design and defect log, R-1 onward
The one rule this codebase enforces on itself
No rule formula may exist in more than one place. Everything lives in rules.mjs,
and tools/check-rules.mjs fails the build if a formula is restated, if an alias
stops being identity-equal to what it aliases, if a constant is re-declared as a
literal, or if an exported rule has no spot-check. The packs used to be built under
one set of numbers and played under another; this makes that impossible to ship.
The build runs all eight guards before it writes anything:
check-rules: OK — 103 rules, 34 files scanned, 3 aliases + 46 constant sets checked, 358 formulas verified
check-kits: OK — 25 roles, 10 trades, 218 catalogue items, every kit key resolves, every posting can use what it carries, every loadout distinct
check-lang: OK — en.json, 1015 keys, no leaf/branch collisions
check-templates: OK — 19 templates compile
check-behaviour: OK — 75 behavioural tests
check-scenarios: OK — 10 scenario files, 78 mechanic tags, every skill named resolves against 62 catalogue entries
check-creatures: OK — 102 actor specs across 8 sources, every characteristic, skill, kit key, talent, species and style resolves, no duplicate keys
check-lethality: OK — 47 creatures, none drifted more than 6 points of wipe rate against the frozen party, 1 new