# Expedition Difficulty Tuning Pass Started 2026-05-15, after the Phase D audit close-out. Sibling to the class-balance pass (`gogobee_class_balance.md`) — same Monte-Carlo philosophy, different target metric. **Class balance answers** "is my class viable?" (parity between classes vs. the same monster tier). **This pass answers** "is the dungeon fair?" (does a tier-appropriate character complete a tier-N expedition at the expected rate?). Same combat engine (`simulateCombatWithRNG`), orthogonal knobs. --- ## Method **Sim harness, not telemetry-first.** A new `internal/plugin/dnd_expedition_balance.go` will run thousands of seeded expeditions through the real autopilot / threat / encounter / combat code and report: - completion % - death % - median days-to-extract - median threat at extract - supply curve (% expeditions that hit Rationing / Severe / Starvation) - combat-encounter count per run - coin/XP earned The harness produces these per (zone, player-level) cell; the regression test asserts the per-tier completion band. **Tier target band** (steered by [[feedback_difficulty_target]] "relatively easy but not too easy", and reflecting that expeditions are multi-day commitments players plan around — losing one should sting but not feel arbitrary): | Tier | Target completion % | Acceptable band | |------|--------------------:|-----------------| | T1 | 80% | 70–90% | | T2 | 72% | 62–82% | | T3 | 65% | 55–75% | | T4 | 55% | 45–65% | | T5 | 45% | 35–55% | Bands are ±10pp around the centerline. Sim is asserted against the band, not the centerline (no overfit). Player-level for each cell = "tier appropriate" per the class-balance kit ladder: T1 → L1-4, T2 → L3-7, T3 → L5-10, T4 → L7-15, T5 → L10-20 (median level per tier). **Out of scope:** - Per-encounter combat parity (covered by `gogobee_class_balance.md`). - Arena difficulty (separate system, separate balance). - Live telemetry tables — deferred; sim is the primary truth source for this pass. We can add counters later if the sim diverges from observed live numbers. --- ## Phases Each phase ≈ 1 session, ships green + committed. ### Phase 0 — sim harness spike Build the minimum harness: - New file `internal/plugin/dnd_expedition_balance.go` exposing `simulateExpeditionWithRNG(profile, seed)` → result struct. - **Critical de-risk: replay the autopilot deterministically.** The ticker is wall-clock driven (`dnd_expedition_cycle.go:38,56` at 06:00 / 21:00 UTC; `expedition_ambient.go:22` every 3h). Harness must inject a virtual clock or call the per-phase advance functions directly (`deliverBriefing`, `deliverRecap`, ambient nudge, harvest autopilot) in tight loop, bypassing the goroutine ticker. **Settle the clock-injection seam in Phase 0** — if this is messy, the whole pass collapses. - DB-touching layers stubbed/in-memory (same trick as class-balance Phase 0). - Sanity test: one cell — e.g. T2 zone at L5 Fighter — runs to completion or death deterministically, returns sensible numbers, 100 trials in <10s. **Exit:** `TestExpeditionBalance_Phase0_Spike` green; commit. ### Phase 1 — full matrix measurement - Build the cell list: every zone × tier-appropriate-level. Per the exploration map, expeditions span zones tagged T1–T5; we measure every zone at its centerline level. - 200 trials/cell (same density as class-balance Phase 1). - Matrix log: per-cell completion%, death%, median days, median extract-threat, supply-curve histogram. - Per-tier mean + spread diagnostic across zones (analogue of the class-balance per-(level,tier) spread diagnostic). - `TestClassBalance_Phase1_FullMatrix`-style permanent test, but only gating on harness-broken pathologies for now (0% completion anywhere at T1, 100% completion at T5). **Exit:** matrix numbers logged; commit with "Phase 1 baseline" note. ### Phase 2b — wounded-entrant nick clamp (shipped) `clampSurpriseNick(rawNick, hpCurrent, hpMax)` in `dnd_expedition_combat.go`: at full HP the raw nick stands; when wounded the nick is capped at `max(1, hpCurrent/5)` so a single nick on a low-HP fighter can't shave more than ~20% of remaining HP. The existing "nick can't KO" guard is preserved. Motivation came from the post-2a tier-lethality trace (`TestExpeditionBalance_Phase2_TierLethality`): every tier had a fingerprint where an over-tier elite left the fighter at 25-50% HP + retreat, then the next standard's surprise nick (3-7 HP, often exceeding the fighter's headroom) pre-empted the combat engine entirely. Capping the wounded-entrant nick separates that cascade from genuine elite-one-shot deaths so Phase 2c can tune the elites with a clean read. Matrix delta vs Phase 2a baseline is small (median encs +0.1-0.2 per cell) — completion% still 0% across every tier — but the tier-lethality trace stretched substantively: T1 trial 0 went 5 → 8 encs / 5 → 7 days; T3 trial 1 ran 18 → 10 encs but visibly survived multiple chained interrupts at low HP that pre-2b would have ended on the nick alone. The remaining deaths are now legible as elite one-shot fights on fresh entries (Hobgoblin Warchief, Green Hag, Roper, Young Red Dragon) — that's the Phase 2c roster signal. **Tuning surface:** the `/5` divisor in `clampSurpriseNick` is the wounded-fighter lethality knob. ### Phase 2 lever sweep (shipped) — negative result Before adding Phase 2c, the two surfaced knobs (`retreatThreatBump`, `clampSurpriseNick` divisor) got swept across a full 3×4 grid (bump ∈ {2, 5, 10} × divisor ∈ {3, 5, 8, 12}) at 200 trials/cell across every zone in the matrix. Wired via `expeditionBalanceProfile.{RetreatThreatBumpOverride, SurpriseNickDivisorOverride}` threaded into `expeditionHarness`; the live caller (`runHarvestInterrupt`) is untouched. Sweep file: `TestExpeditionBalance_Phase2_LeverSweep` in `expedition_balance_test.go`. `-short` skips. **Outcome:** every one of the 24,000 trial-cells reports 0.0% completion / ~100% death. The two knobs are inert on the headline metric — even the gentlest combo (b=2, d=12) cannot lift any tier off the floor. Median days-to-end stays at 2–3 across the grid with median 2.6–7.3 encounters before death. **Read:** confirms the post-2b tier-lethality trace — deaths are fresh-entry elite one-shots (Warchief @ HP19/20, Hag @ HP41, Roper, Young Red Dragon), not chained-interrupt cascades. The two levers target the cascade path that's now mostly resolved; they have no remaining death-fraction to convert. Phase 2c (roster dilution) is justified rather than premature. ### Phase 2c — roster gate (shipped) Promoted one mid-tier alt to `IsElite: true` in every zone whose elite pool was a single SpawnWeight=1 boss (`internal/plugin/dnd_zone.go`). The boss stays in the pool; weighted dilution means the InterruptElite bracket no longer auto-picks the over-tier boss. `pickZoneEnemy` also excludes the promoted entry from the standard pool, lowering standard encounter difficulty by removing one mid-difficulty option from non-elite brackets (acceptable: each zone still has 3-4 standard entries left). Crypt-Valdris was already dual-elite (wight + flameskull) and was left alone. | zone | promoted alt | boss (untouched) | |--------------------|-----------------------|--------------------| | goblin_warrens | worg (SW=3) | hobgoblin_warchief | | forest_shadows | owlbear (SW=4) | green_hag | | sunken_temple | aboleth_thrall (SW=3) | water_elemental | | manor_blackspire | vampire_spawn (SW=3) | revenant | | underforge | salamander (SW=3) + fire_elemental (SW=3) | helmed_horror | | underdark | drow_elite_warrior (SW=4) | roper | | feywild_crossing | night_hag (SW=3) | fomorian | | dragons_lair | dragonborn_cultist (SW=3) | young_red_dragon | | abyss_portal | hezrou (SW=4) | marilith | **Phase 1 matrix delta (200 trials/cell, Fighter, tier centerline):** goblin_warrens 0% → **3.0%** completion (first non-zero T1 reading since Phase 0); sunken_temple 0% → 0.5%; dragons_lair death% **100% → 60%** with 40% now starve (fighter survives the elite-spawn path long enough to run out of supplies — different failure mode); underdark death% 100% → 90% (10% starve); feywild_crossing 100% → 92% death (8% starve). T3 manor_blackspire / underforge still 100% death — the remaining death pressure there is the post-2b chained-standard path, not the elite roll. Tier-lethality trace cross-check (`Phase2_TierLethality`) shows the new alt-elites actually spawning and being winnable: underdark trial 1 now opens with `Drow Elite Warrior` (won), reaches the Roper at turn 6, retreats, then dies on a Hook Horror nick — a substantively longer arc than the pre-2c fresh-entry Roper one-shot. Dragons_lair trials similarly show `Dragonborn Cultist` as a winnable elite stop before the dragon roll lands. Stat-block tuning of the bosses themselves is off-limits per the Phase 3 constraint (bestiary is shared across systems). ### Phase 3 — global lever tuning Tune the knobs that affect every zone uniformly: - **Daily threat drift** (`dnd_expedition_threat.go:87` — base +3/day). - **Threat band thresholds** (Quiet/Stirring/Alert/Hostile/Siege — `dnd_expedition_threat.go:70-82`). - **Supply burn multipliers** (`dnd_expedition_supplies.go:43-56` — T1×1 → T5×3). - **Surprise-round damage floor** (`dnd_expedition_combat.go:184`). - **Encounter bracket thresholds** (`dnd_expedition_combat.go:39-44` None/Noise/Standard/Elite/Patrol). - **Camp mods** (`dnd_expedition_night.go:85-92`). Goal: every tier centerline lands within ±5pp of target. Bands stay ±10pp. #### Phase 3-A — elite-bracket + drift sweep (shipped) Wired two harness overrides (`EliteInterruptThresholdOverride`, `ThreatDriftBaseOverride`) and swept a 3×3 grid (elite ∈ {17, 19, 23} × drift ∈ {1, 3, 5}) over the Phase 1 matrix. Test: `TestExpeditionBalance_Phase3_GlobalLeverSweep`. **Strong partial positive.** The elite-bracket threshold is the dominant lever for T1–T3; threat drift is a small modulator on top. | (elite, drift) | T1 mean | T2 mean | T3 mean | T4 mean | T5 mean | |----------------|--------:|--------:|--------:|--------:|--------:| | 17, 1 (more elites) | 0.5% | 0.0% | 0.0% | 0.0% | 0.0% | | 19, 3 (live) | 3.0% | 0.2% | 0.0% | 0.0% | 0.0% | | 23, 1 (rare elites) | **24.0%** | **7.2%** | **1.8%** | 0.0% | 0.0% | | 23, 3 | 16.5% | 4.0% | 2.0% | 0.0% | 0.0% | | 23, 5 | 11.8% | 3.2% | 0.2% | 0.0% | 0.0% | Best cell at e=23/d=1: goblin_warrens 40.5%, sunken_temple 14.5%. Still well below the T1 70-90% / T2 62-82% target bands — the lever moves the needle in the right direction but cannot land any tier on-band alone. **T4/T5 fingerprint changed but didn't lift.** At e=23 the dragons_lair death-fraction drops from ~60% → 24% but starvation climbs to 75% — the fighter now survives elites long enough to run out of supplies. T4 (underdark/feywild) likewise sees death drop and starvation rise. Indicates a second lever is needed for the higher tiers: either standard-fight survivability (surprise-nick floor / standard roster density) or supply margin. **Next:** Phase 3-B sweeps surprise-round nick and supply-burn knobs on top of e=23/d=1 to push T1-T3 toward target band and lift T4-T5 off the floor. #### Phase 3-B — nick-floor + supply-burn sweep (shipped) Wired two more harness overrides (`SurpriseNickFloorOverride`, `SupplyBurnRatePctOverride`) and swept a 3×3 grid (floor ∈ {0, 1, tier (=live)} × burn% ∈ {50, 75, 100 (=live)}) on top of the Phase 3-A best cell (e=23, d=1). Test: `TestExpeditionBalance_Phase3B_NickSupplySweep`. **Strong partial positive for T5 supply margin; nick-floor lever inert.** Tier-mean completion (Fighter, centerline level, 10 zones × 200 trials): | (floor, burn%) | T1 mean | T2 | T3 | T4 | T5 | |----------------|--------:|----:|----:|-----:|-----:| | 0, 50 | 20.8% | 5.0%| 3.8%| 7.5% | 29.5%| | 0, 75 | 26.5% | 6.0%| 2.8%| 9.0% | 0.0% | | 0, 100 | 25.8% | 5.0%| 3.0%| 0.0% | 0.0% | | 1, 50 | 25.5% | 6.5%| 1.8%| 8.5% | 27.8%| | 1, 75 | 28.5% | 6.2%| 4.0%|11.5% | 0.0% | | 1, 100 | 26.8% | 7.5%| 2.5%| 0.0% | 0.0% | | tier, 50 | 26.8% | 6.2%| 2.5%| 7.8% | 27.5%| | tier, 75 (live floor) | **29.5%** | **7.8%** | 3.0% | **12.8%** | 0.0% | | tier,100 (live)| 28.5% | 6.8%| 3.0%| 0.0% | 0.0% | Three readings: 1. **Supply burn is the T5 unlock.** dragons_lair completes ~55% at burn=50 (versus 0% at burn=75/100) — the fighter survives elites but starves en route. burn=75 isn't enough margin; burn=50 converts the starvation-out into a completion. 2. **Supply burn is the T4 modulator.** underdark/feywild step from 0% (burn=100) → 12% (burn=75) → 8% (burn=50). The burn=75 peak is the sweet spot; halving further leaves the fighter alive *into* more elite fights, where it dies in combat instead. 3. **Nick-floor lever is inert.** Across all burn levels, dropping the surprise-round floor from `tier` → `1` → `0` moves T1-T3 means by at most ~3pp. The wounded-clamp (Phase 2b, `clampSurpriseNick`) already eats the chip-damage budget on repeat entries; the raw floor only matters on the first fresh-HP swing, which the engine recovers from. **Recommendation: discard this lever from the live-tuning candidate list.** **T2-T3 wall persists.** Even at the best (floor=tier, burn=75) cell: T2 reads 7.8% (target 62-82%) and T3 reads 3.0% (target 54-74%). forest_shadows T2, manor_blackspire T3, and abyss_portal T5 sit at ~0% across every combo — these are zone-specific outliers, not addressable by any global lever. **Phase 4 (per-zone outlier pass) is the next move.** **Next:** Phase 4 walks the matrix zone-by-zone. The shipped Phase 3 sweep already names the worst offenders (forest_shadows T2, manor_blackspire T3, abyss_portal T5, crypt_valdris T1); each needs a diagnostic trace (boss stat-block, roster mix, supply DC) to pick the right per-zone tool from `Phase 4`'s list. Optional: revisit shipping the burn=75 global if Phase 4 outlier fixes leave T4 still stuck. ### Phase 4 — per-zone outlier pass After globals settle, the matrix names outlier zones — tiers where one zone reads dramatically off-band while sibling zones are fine. Per-zone tools: - `SpawnWeight` / `IsElite` flags in zone rosters (`dnd_zone.go:100`). - Boss stat tuning in zone definitions. - Resource DCs (affects harvest interrupt roll). - Per-zone loot table density (downstream economy impact — flag if significant). Constraint: do not touch monster stat blocks (those belong to the bestiary, shared across systems). Tune the roster + zone-level knobs, not the monsters themselves. #### Phase 4-A — outlier diagnostic (shipped) Added a structured per-fight trace hook (`traceFightStruct` + `harnessFightTrace`) alongside the existing string `traceFight`; both fire from the same `runHarnessFight` site so the human log and the structured aggregate stay in sync. Test: `TestExpeditionBalance_Phase4A_OutlierDiagnostic`. For each of the four outlier zones it pairs against the healthy sibling at the same tier (goblin_warrens, sunken_temple, underforge, dragons_lair), running 200 trials each on the Phase 3-B best cell (e=23, d=1, burn=50) and reporting per-monster appearances / win-rate / avg HP loss / kill attribution + day-of-end histogram. Findings — each outlier had one or two miscategorised entries that Phase 2c's single-boss-elite dilution sweep had skipped: - **crypt_valdris**: dual-killer elite pool (Wight 99k, Flameskull 68k); Phase 2c had skipped this zone as "already dual-elite," but both elites are over-tier for T1. - **forest_shadows**: standard pool too lethal — Displacer Beast (38% win, 53k) + Bandit Captain (57% win, 48k). - **manor_blackspire**: Wraith on standard slot (45hp loss per win, 85k). - **abyss_portal**: Nalfeshnee mis-classified standard (CR-13, 2.8% win, 86k) + Vrock standard at 43hp loss per win. #### Phase 4-B — roster re-classification (shipped) Per-zone roster tweaks based on Phase 4-A's attribution. No monster stat-block touches. - crypt_valdris: dropped flameskull (lives in underforge T3); promoted specter to IsElite SW=3 as the soft dilutor. - forest_shadows: promoted Displacer Beast + Bandit Captain to IsElite; Owlbear SW 4→2 so the 4-elite pool dilutes evenly. - manor_blackspire: promoted Wraith to IsElite (joins Spawn+Revenant). - abyss_portal: promoted Nalfeshnee + Vrock to IsElite (collapses standard pool to Quasit alone, ≥99% win). Outlier-vs-sibling completion (Phase 3-B best cell, 200 trials): | Zone | Before | After | Sibling | |------|-------:|------:|--------:| | crypt_valdris T1 | 8.5% | **46.0%** | 45.0% | | forest_shadows T2 | 0.0% | **7.5%** | 13.0% | | manor_blackspire T3| 0.5% | **14.5%** | 3.0% | | abyss_portal T5 | 0.0% | **25.0%** | 57.5% | Phase 3-B tier mean (b=50, f=tier) before → after: T1 26.8% → 44.0% (+17pp), T2 6.2% → 10.0% (+4), T3 2.5% → 8.5% (+6), T4 unchanged, T5 27.5% → 41.0% (+14). **Exit (partial):** the four off-band outliers are no longer outliers — every per-zone cell is within the spread of its tier siblings. The Phase 4 plan's stricter exit ("all per-zone cells within target band") is **not** met: T2/T3/T5 sibling pairs still sit below band (T2 7-13% vs 62-82%; T3 3-14% vs 54-74%; T5 25-57% vs 36-56%). That gap is tier-wide, not zone-specific — both zones at each problem tier underperform together — so no further per-zone tool will close it. Phase 5 (or a follow-up tier-wide pass) needs to take over. **Next:** Phase 5. Candidate moves are tier-wide: revisit player gear-tier mapping at T2/T3 (the centerline level vs gear ladder, see `phase1TierCenterline`), reconsider the elite-bracket threshold per-tier instead of global, or ship `burn=75` as the new live global since Phase 4-B already converted T4 to playable at b=50. ### Phase 5 — tier-wide pass (T2/T3/T5 under-band) Phase 4-B closed the per-zone outliers but left T2/T3/T5 sibling pairs below the target band as a *tier-wide* gap. The plan doc's three candidate moves (gear-tier centerline remap, per-tier elite threshold, ship `burn=75`) needed disambiguation before any of them got pulled — hence a measure-first sub-phase. #### Phase 5-A — tier-wide sensitivity sweep (shipped) `TestExpeditionBalance_Phase5A_TierWideSensitivity` runs the 6 under- band zones (T2: forest_shadows + sunken_temple; T3: manor_blackspire + underforge; T5: abyss_portal + dragons_lair) through three one-axis sweeps with the other two levers held at Phase 3-B best (e=23, d=1, burn=50): player level ±2 around tier centerline, elite threshold ∈ {18, 23, 28}, supply burn pct ∈ {40, 50, 60}. 200 trials/cell × 6 zones × 9 cells = 10.8k trials; runs in <1s. Numbers (200 trials/cell, comp%): ``` T2 (band 62-82%) L forest=0→6.5→19 sunken=0→13.5→34.5 STRONG slope E forest=0.5→9→8 sunken=0→14.5→13 saturated @23; 18 collapses B forest=3.5→7→6.5 sunken=14→15.5→11 inert T3 (band 54-74%) L manor=3→10.5→13.5 under=0→4→8.5 clear slope E manor=0→9.5→9.5 under=0→3→4 saturated @23; 18 collapses B manor=13→9.5→9.5 under=2.5→4→2.5 inert T5 (band 36-56%) L abyss=21.5→28.5→32 dragons=60→60.5→53 gentle; dragons in-band E abyss=1→28.5→31 dragons=10→60.5→57.5 saturated @23; 18 collapses B abyss=27.5→28.5→0 dragons=59→60.5→0 burn=60 STARVE CLIFF ``` **Reading:** - **Player level is the dominant lever at T2/T3.** Every +2 levels lifts completion meaningfully; the elite gate and supply burn are inert or actively harmful around the Phase 3-B baseline. - **Elite threshold is already at its sweet spot at e=23.** Going to e=18 floods elites and collapses every tier; e=28 is flat. The per- tier-threshold candidate from Phase 4 close-out is killed: there's no per-tier value to be found in the explored range. - **`burn=75` globally is killed.** burn=60 alone produces 36% / 61% starve at T5; burn=75 would be catastrophic. The Phase 3-B negative result holds tier-wide. burn must stay ≤50. - **T5 dragons_lair is already in-band** at the baseline (60.5%). The T5 tier-wide gap is really an abyss_portal gap (28.5%); the Phase 4-B re-class lifted it from outlier to "low-but-not-isolated," but it still sits below band by itself. - **The level-bump path has a catch.** L7 at T2 (still inside the L3-7 design range and gearTier=2) only reaches ~27% mean — still well below the 62-82% band. Closing T2 to band likely requires a *cross-gearTier-boundary* centerline (T2 → L9 = gearTier 3) and/or a player-side combat-math adjustment, not just a within-bracket centerline shift. That's a design call, not a knob twist. **Next:** Phase 5-B is a design choice between three concrete moves that the measurement now backs: 1. **Cross-bracket centerline bump** for T2 (→ L9) and T3 (→ L13), plus T5 abyss-only level tweak. Lifts player gear bracket into the next tier; closes the band gap directly but is a player-side power move that affects the live game (chars at the centerline level keep their existing gear; centerline only governs the harness's measurement cell). The change is *in the harness*, but it admits the live difficulty target was wrong for these tiers — Phase 5-C would then carry it back to the live gear-acquisition curve. 2. **Player combat-math retune** at T2/T3 (HP scaling, proficiency curve, attack-bonus floor) — bigger lift, touches the class-balance harness too, deserves its own pass. 3. **Lower the band target** for T2/T3/T5 to ~30-50% mean and accept that completion is meant to be hard. This is the "do nothing" option dressed up as a design decision; surfaces the question of whether the original 70% T2 target was ever the right number. Recommend option (1) for Phase 5-B since the harness already measures it cleanly and the data points at it; option (3) is the fallback if the cross-bracket numbers still don't close the band. #### Phase 5-B — player power floor + Phase-3 winners shipped The Phase 5-A read named player level / gear-tier centerline as the dominant lever at T2/T3 but flagged that even max-of-range within the gear bracket missed the band. Three design options were on the table: cross-bracket centerline bump, **player combat-math retune**, or lower the band target. The user picked combat-math retune ("fairly breezy with some death — not a ton") — option (2). On reflection this was the only one of the three that actually moves *live* difficulty (cross-bracket centerline only moves the harness number; lowering the band is the "do-nothing" fallback). The shipped lift, in five small pieces: 1. **`computeMaxHP` ×1.5** (`dnd.go: phase5BHPMult`). The HP curve is uniformly scaled so every class/level lifts together — preserves the class-balance harness's in-tier spread assertion. Migration `bootstrapPhase5BHPRefresh` walks `dnd_character` once at startup to refresh existing rows; idempotent via `db.JobCompleted`. 2. **Combat-stat player floor** (`dnd_combat.go: applyPhase5BPlayerFloor`): +3 AC, +3 AttackBonus, +3 weapon.MagicBonus (damage). Applied at the END of `applyDnDEquipmentLayer` (so the AC override from `computeArmorAC` doesn't stomp it) AND inside `buildHarnessPlayer` so live and harness measurement agree. 3. **Elite bracket 19 → 23** (`dnd_expedition_combat.go: resolveCombatInterrupt`). Case order: Elite (≥23) before Patrol (≥22) so a 23+ total prefers the single dangerous fight over the patrol-flavored standard pick. Elite is now effectively a *high-threat* event reachable only via the +1-per-20-threat-above-40 mod — base d20+tier+ranger maxes at ~21. Phase 4-B's elite-pool monsters still appear; just less often. 4. **Threat drift base 3 → 1** (`dnd_expedition_threat.go: dailyThreatDrift`). Slows the threat clock so players have the days they need to extract before threat tips zones into the new 23+ elite band. 5. **Daily supply burn × 0.5** (`dnd_expedition_supplies.go: phase5BDailyBurnRatePct`). `applyDailyBurn`'s default now passes 50; `applyDailyBurnP` keeps its rate-parameterized form for the harness. Also applied in the temporal-override branch (`dnd_expedition_cycle.go`) so tidal / unraveling days scale by the same 0.5× — otherwise those days would be disproportionately harsh against the new baseline. The harness reflects all five (`expedition_balance.go` reads `phase5BDailyBurnRatePct` as the default-burn fallback when the override knob is zero). Phase 1 matrix on the shipped baseline, Fighter @ tier-centerline, 200 trials: ``` T1 87.8% spread 1.5 (crypt 89, goblin 87) ⬆ band 70-90 — IN BAND T2 74.0% spread 12 (forest 80, sunken 68) ⬆ band 62-82 — IN BAND T3 43.2% spread 8.5 (manor 39, underforge 47) ⬇ band 55-75 — UNDER T4 71.8% spread 25.5 (feywild 59, underdark 88) ⬆ band 45-65 — OVER (breezy) T5 ~57% (dragons 78, abyss 38) ⬆ band 35-55 — borderline ``` Four of five tier means land at or above band-center, matching the "fairly breezy with some death" target. **T3 remains the hump** — both manor and underforge sit ~40-50% completion, killing 50-60% of the time. Phase 4-B already promoted T3's worst killers (Wraith) to elite, so the standard-pool deaths are now the irreducible part. T4's wide spread (feywild 59 vs underdark 88) means feywild still has a roster-side asymmetry that warrants a Phase 4-B-style pass. **Test debt cleaned:** 13 unit tests in `combat_stats_test.go`, `dnd_test.go`, `dnd_xp_test.go`, `dnd_equipment_profiles_test.go`, `dnd_expedition_supplies_test.go`, `dnd_expedition_cycle_test.go`, `dnd_expedition_extract_test.go`, `dnd_expedition_region_cmd_test.go`, `dnd_expedition_combat_test.go`, `dnd_expedition_threat_test.go`, `dnd_expedition_temporal_test.go`, `expedition_balance_test.go` were pinning the pre-Phase-5-B numbers; updated to the shipped values with comments noting the cause. **Exit:** Phase 5-B closed-out the user's primary target ("make it breezy"). T1/T2/T4/T5 mean in or above band; T3 remains the design hump and is fine for "some death" tier shape. Remaining work (Phase 5-C+) is T3 roster polish + feywild T4-spread fix — separate session. ### Phase 6 — optional MAD / second-order If post-Phase-3 the bands hold but feel wrong subjectively (e.g. "median days too short", "no expedition ever hits Siege"), add a secondary assertion on median-days-to-extract or extract-threat. Phase 3 may also surface a request to expose a difficulty knob to operators (env var or admin command); scope that here if it comes up. --- ## Open questions - Should the babysit perk be on or off in the sim? Pick one and document; both as separate cells doubles matrix size for diminishing insight. Default proposed: **off**, since it's a discovery-mechanic buff ([[feedback_npc_buffs_are_secret]]) — players who find it earn extra margin, not the baseline. - Pardon proc (33% @ chat 20+): include in sim, but at a fixed chat-level assumption (chat 15 = no pardon, since most fresh runs haven't hit the threshold). Decide in Phase 0. - Sovereign reprieve: skip in sim — it's gated on full set equipped and is a one-shot per cooldown. End-game-only; not part of the baseline difficulty. - Multi-region zones (E4): does the sim need to walk all regions in one expedition, or pick one region per run? Probably full walk for realism. Settle in Phase 0. - DM mood: starts at 50; drifts via combat outcomes. Let it drift naturally in the sim, do not pin. --- ## Deliverables checklist - [ ] `internal/plugin/dnd_expedition_balance.go` (sim harness) - [ ] `TestExpeditionBalance_Phase0_Spike` - [ ] `TestExpeditionBalance_Phase1_FullMatrix` (becomes the permanent regression gate after Phase 2 tightens it) - [ ] Tuning commits per phase - [ ] One-line update to `MEMORY.md` + project memory pointer