- *Research note (not a rule).* [Reference: Electricity in Water, REF101 r2](https://open-wiki.tail2e4d02.ts.net/Reference/Electricity%20In%20Water?revision=10e0a37), by the team's Reference Researcher, documents real electrofishing response zones: attraction toward the anode at low field strength, forced swimming toward it as the field grows, immobilisation at roughly ten times the attraction threshold. That is the same shape as this page's beacon (lure) and coil (stun): one physics at two intensities, which the Design Document r3 also cites as grounding. It supports the fiction; it does not set any number here, and the game's rule stays W1 as written.

2. **Invitation.** The lit branch is where the next dispatch enters, and lighting the yard is the only way the panel opens H. The branch you want open is the branch the next surge comes to.

| Understand | Two cables leave each position of P, a thick one and a thin one, and run side by side to B1, and to B2 and on to H. At a dispatch the pulse is seen running the thin cable before the beacon flashes. P's three positions carry no words: two cable headings and a closed position. The forecast shows a countdown, an intake marker, and each entered crowd's current target. Switching moves the marker at once, and moves the crowd: the rule can be learned by watching a pulse run the cable and the surge's turn, or by switching and watching both the marker and the crowd respond. The notebook records what was seen, in the player's own words. |

| Experiment | Set Yard. B2 lights, H opens, the intake marker jumps to I2 with the countdown running, and the crowd at B1 begins across the junction toward B2. Retreat to R1 or D1 and watch, or move now. Off instead darkens both and moves the marker to the sluice. |

| Change later play | Each dispatch reopens the choice: keep Causeway and haul through the culvert to a dark, closed yard; set Yard early, before any crowd exists, to walk the empty causeway to the junction while the yard is hot; or set Yard with a crowd already at B1 to clear the causeway at the cost of the interior route and the hall. Turned signs (W4) now read as a route. |

**The reachable answer (spoiler; proposal).** Inside the pump hall, beside the hall's dead pump, a crew tally board: rows of marks per surge sent to the causeway; a last row with one mark to the yard and a line under it; a district plan with the refuge signs crossed out and a route inked through the culvert to the interior. The last crew fed the evacuation route to keep working the yard, turned the signs to mark their own way, and left the panel on Causeway for whoever came after. It changes action: the inked route and W4 point into the interior.

**Knowledge gate, not item gate.** The panel works on expedition one; what changes is knowing what it does. Loadouts change how well a choice can be exploited, never whether it can be made.

**Fair recovery.** Death: rescue without cargo; notebook, map, and observed facts persist; no deduction is granted. Missed clue: B1 is lit on every arrival and pulses every dispatch; the culvert is visible from the yard bank; the marker-and-crowd response to a switch is an independent second path. Hints escalate from "the two beacons differ" to "switch, then watch the forecast and the crowd". Withdrawal never requires solving this (scene 1).

**Scene 1 — untouched panel, first expedition, retreat.** Panel on Causeway, D1 held. Surge 3 enters at I1 and gathers at B1, the far north end. The surveyor, at the yard deposits, takes X2 into the culvert, walks south under the causeway to X1, crosses the short open stretch to D1, a hard stop. No beacon stands on that route, so no crowd is drawn along it; what is met is the causeway crowd's press near the causeway head, stragglers, and organisms inside pursuit range (the Design Document's expedition one shows the shape of it at nine minutes, one hit taken). The claim "withdrawal never requires solving this" therefore holds only under a stated constraint, which the draft should carry as a tuning bound: **on expedition one, the press of an untouched-panel causeway crowd must not reach the causeway head before the evacuation window closes.** A proposed bound, not a proven value.

**Scene 2 — inside the pump hall when power ends, then when the next surge arrives.** The surveyor set Yard, crossed to the hall while the crowd was still crossing the junction, and is reading the tally board. *Power ends* (the panel is switched to Causeway or Off, or a coil-opened H times out): H blinks for three seconds and closes, never on an occupant; anyone inside is shut in. Rule, the Design Document's, adopted here: **a hatch closes when its branch loses power, never on an occupant, and can be cranked open from inside in ten seconds without power.** No mystery solution is needed to leave, and the recovery takes exactly long enough to matter. *The next surge arrives* with Yard still lit: it enters at I2 and gathers in the channel mouth in front of the hall, standing in water. From inside, the surveyor is behind H with the crowd outside it. Choices: hold the doorway, where pursuit brings them in one at a time, at a cost in health; wait for the press to thin the door and lose surge time; or, with a coil and insulation, step to the channel's edge inside the doorway and discharge, which is the electrician's whole reason for being there. Switching the panel from inside is impossible, because P is at the causeway head.

**Motive, no upkeep.** The colony is a dozen people on the one dock the pump keeps dry. The pump runs on salvage already banked; nothing is charged per expedition, there is no decay between sessions, and repeated failed expeditions lose only their own cargo. What salvage buys is change: a dock held dry instead of the other, a workshop, the forecast relay, and the ending itself. A colony that stops hauling is not drowned; it is stuck. The surveyor goes in because the crew before them went in and did not come back, and because the district's own machinery is what is sending the Flood at the refuge route.

**The title.** "Hold the Flood" is the owner-supplied working title and is kept as such; final naming is the owner's and is not locked (D017; this page's earlier revisions wrongly listed it under owner requirements, which Clarity Q37 caught). In A it means holding the enemy mass off the refuge: the dock, the causeway signed as the way out, and eventually the district. The pump holds water; the panel, the beacons, and the surveyor hold the Flood. The Flood is never water.

**Three tiers on one district, each a recombination of the same rules.** *Tier 1, the false refuge* (designed above): learn that power is key and lure; the panel is the lever. *Tier 2, the junction and the interior, "what they went in for":* the junction gate GJ is on a circuit the panel never reaches. Evidence: valve V beside it, drawn open on the inked plan and found shut; a lamp on the junction pool that lights whenever the yard channel is energised while V is open. Inference: joined water carries power, and therefore attraction, across the district, so the crew could open GJ from the yard without the panel. Experiment: open V and light the yard at the panel; the pool's lamp lights and GJ opens for as long as the yard is lit, with the yard hot behind you and crowds drawn toward the junction while its lamp is lit. Or leave V shut and discharge the coil into the pool: GJ opens quietly, without lighting a beacon, for the seconds the charge lasts. The coil buys stealth, not access (REV102-6). Consequence: entering tier two needs no module, and every way in has a price the player can read. Behind GJ: the second tally board and the crew's note of the relay room's valve sequence. Keep tier 3 a knowledge gate: the relay room opens by the same current rule and that note, not by a found key item. *Tier 3, the relay room, "what calls the Flood":* the timer itself, at the sluice's head. The final choice, each one an expedition-ending act with a different persistent district: **shut it** (no more dispatches; the Flood enters only by the sluice, unannounced: honest and harder), **fix it** (weld the panel to one branch for good: one dock safe forever, one branch lost), or **hold it** (leave it running and keep steering: the status quo, chosen). Free expeditions continue after any ending. None of this adds a machine family: valves, lamps, beacons, hatches, and the relay already exist.

**Early, middle, final (illustrative; the expedition count is a proposal, not coverage).** Early: the panel, the culvert, the yard; hauler loadouts; the first colony repair. Middle: G and the interior; valves; the held-dock switch; electrician and shepherd loadouts; the tally board and the inked route. Final: the relay room and the choice. A rough twelve to twenty expeditions is the lead's number to defend in DES102 against the content above; this page supplies the tiers, not the count.

Nothing is open for this role. Draft r3 aligned to this page's r10 and applied its items 1–7 (gravity-drain culvert and dead pump; both docks share the bypass and the asymmetry is water; the press-rate bound as a tuning constraint; each crowd's target on the forecast; the turned-sign rule; the relay room by valve sequence, not a key; the chain rows lifted). Draft r4 completed REV102 issues 3 and 5 (the flash observable, now mirrored in W1 and the Understand row above; the bound restated in section 15) and settled the topology. r11's two items were overtaken: r3 chose *press* and *pursuit range* and the three-part dock cost. Division of sources from here: the Design Document's sections 2 and 4 are canonical for topology and crowd behaviour; this page is canonical for W1–W4 and the mystery chain, which section 9 mirrors; if they drift, the drift is reported here and fixed in one place, and no topology change is made on either page before it is agreed on this one.

- **S3 Live evidence** — new clues, panel switches, and their verification happen in the running world.

One district reused before and after discovery: two docks, causeway, culvert, yard, pump hall, junction platform, sluice, interior and relay room, one panel, two fixed beacons, two devices, a forecast overlay, a tally board and plan, one valve, and wear and sign props (one sign rotated for W4). Evidence types: light state, cable path, wear, a turned sign, an unlabelled panel, a map marker, a crowd's visible target. No compatible free asset set or terms are verified; plain-text inspection is the fallback for props; readable live crowd cues are the lead's Finding 5 table. No custom asset creation is proposed.

r7 and Design r4–r5 used a sight-limited path (a beacon pulls only within its glow) so that the panel could never move an arrived surge. PMR001 set it aside for the simpler district-wide rule above, priced honestly, and PMU002 confirmed that choice after considering the alternative (Brief D016): one visible change has a direct consequence in an existing crowd, and the separate dispatch signal preserves entrance predictability. The decision is made for this draft and remains open to an argued revision; the sight-limited wording is in [r7](https://open-wiki.tail2e4d02.ts.net/Hold%20the%20Flood/World%20and%20Mystery?revision=fa3eb1b), and the Design Document presents it as the labelled alternative and owner decision 3. **This role's position, since a register on this wiki notes that nobody has stated one:** if asked, prefer the sight-limited model, for the reasons given in r7 item 3 (a planning-tool panel keeps the forecast marker always true, keeps the mystery's fairness independent of where a shepherd stands, and needs no panic-switch pricing); the district-wide model is consistent and honestly priced, and the difference is which game the owner wants at the panel. This page is on D013/D016; the preference is recorded, not applied, and a future argument can reopen it.

Task WLD102, In review at r12 per Tasks PMU002; artifact World and Mystery r14 (supersedes r13 a8a3f4f and earlier). No canonical decisions changed by this role; D016 applied (no text change needed), D017 applied (title relabelled), D015 applied (citations relabelled). r14 changes no rule and no chain text. r13 aligned the tier-two door to Design Document r6 / REV102-6 (two sentences). r12 aligned to Design Document r4, mirrors its flash observable in W1 and the chain, removes this page's duplicate map in favour of a link and a notation key, records that nothing from REV102 r1 or the r1–r3 checks remains open for this role, and states this role's position on the routing model without changing the applied baseline. r8 delivered: items 1 and 2 (W1/W2 under PM's model; map; crowd behaviour; the five-part price of the panel; re-derived dock-choice consequence; both scenes; hatch-closure and recoverable-exit rule; culvert account unified as a gravity drain, item 6) and item 5 (motive without upkeep; title kept and related to holding enemies off the refuge; three tiers and an ending on the existing district). Evidence: written reasoning against Tasks ee938e6, Brief 3cf14c7, Design b030c98, Design Review a892274; no player data. Risks, unvalidated: a live-lever panel may dominate if the crossing route and shut door are too cheap; crowd thinning and proximity radius are balance levers with no numbers; readable crowd targets on a crowded screen. Handoff: none open to the lead from this page; the Design Document's section 9 may re-lift the Understand row from r12 if it wants the notation to match. Next for this role, per Tasks PMU002: check any DES103 change that affects clues or rules against the exact integrated revision, without reviving older map variants; otherwise post nothing. Q37 is marked answered on the Clarity page at this revision.

**Routing decision: answered.** Brief D016 confirms D013 after considering the sight-limited alternative; this page has been on D013 since r8, so nothing changes, and the standing request in r9–r13 is closed. The External Critique and the other four contributions are team work since D015; REF101 is cited above as research, EXT101's title finding is answered by D017 and this revision.