Adv 2.0 D&D Phase 11 D4b: Tier 3-5 trap catalog

Adds tier3TrapCatalog (Antimagic Field, Necrotic Miasma, Symbol of
Death, Planar Rift) per design doc §6 Tier 3-5 table. Tiers 3, 4,
and 5 share this pool — the doc lumps them together. Antimagic
Field uses a new SuppressesMagic flag (no damage, narrative
suppression beat); the other three deliver dice damage and skip
the unmodelled secondary effects (max-HP debuff, drop-to-0,
teleport) for a later phase.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/plugin/dnd_zone_combat_test.go

@@ -388,6 +388,125 @@ func TestRollTrapDamage_TripwireZero(t *testing.T) {
 	}
 }
 
+// ── Phase 11 D4b — Tier 3 trap catalog ──────────────────────────────────────
+
+func TestPickZoneTrap_Tier3UsesTier3Catalog(t *testing.T) {
+	zone, ok := getZone(ZoneManorBlackspire)
+	if !ok {
+		t.Fatal("manor_blackspire zone missing")
+	}
+	if zone.Tier != ZoneTierJourneyman {
+		t.Fatalf("manor_blackspire expected tier 3, got %d", zone.Tier)
+	}
+	seen := map[ZoneTrapKind]bool{}
+	for room := 0; room < 64; room++ {
+		tr, ok := pickZoneTrap(zone, "t3-run", room)
+		if !ok {
+			t.Fatalf("pickZoneTrap !ok at room %d", room)
+		}
+		if tr.Tier != ZoneTierJourneyman {
+			t.Errorf("tier 3 zone picked tier %d trap (%s)", tr.Tier, tr.Kind)
+		}
+		seen[tr.Kind] = true
+	}
+	if len(seen) < 2 {
+		t.Errorf("expected variety across 64 rooms in tier 3, only saw %d kinds: %v", len(seen), seen)
+	}
+}
+
+func TestTier3TrapCatalog_AllValid(t *testing.T) {
+	if len(tier3TrapCatalog) < 4 {
+		t.Fatalf("tier 3 catalog should have at least 4 traps, got %d", len(tier3TrapCatalog))
+	}
+	for _, tr := range tier3TrapCatalog {
+		if tr.Tier != ZoneTierJourneyman {
+			t.Errorf("trap %s tagged tier %d, expected 3", tr.Kind, tr.Tier)
+		}
+		if tr.Display == "" || tr.Trigger == "" {
+			t.Errorf("trap %s missing display/trigger text", tr.Kind)
+		}
+		nonDamaging := tr.AlertsEnemies || tr.SuppressesMagic
+		if !nonDamaging && (tr.DamageDiceN == 0 || tr.DamageDiceD == 0) {
+			t.Errorf("trap %s deals no damage and is not alarm/suppression", tr.Kind)
+		}
+		if tr.DetectDC < 16 {
+			t.Errorf("trap %s detect DC %d looks tier 2; tier 3 should be 16+", tr.Kind, tr.DetectDC)
+		}
+	}
+}
+
+func TestRollTrapDamage_NecroticMiasmaIn6d6Range(t *testing.T) {
+	var miasma zoneTrapDef
+	for _, tr := range tier3TrapCatalog {
+		if tr.Kind == TrapNecroticMiasma {
+			miasma = tr
+			break
+		}
+	}
+	if miasma.Kind != TrapNecroticMiasma {
+		t.Fatal("necrotic miasma not in tier 3 catalog")
+	}
+	for room := 0; room < 64; room++ {
+		dmg := rollTrapDamage(miasma, "miasma-run", room)
+		if dmg < 6 || dmg > 36 { // 6d6 range
+			t.Errorf("miasma damage out of 6..36 range at room %d: %d", room, dmg)
+		}
+	}
+}
+
+func TestRollTrapDamage_AntimagicFieldZero(t *testing.T) {
+	var anti zoneTrapDef
+	for _, tr := range tier3TrapCatalog {
+		if tr.Kind == TrapAntimagicField {
+			anti = tr
+			break
+		}
+	}
+	if anti.Kind != TrapAntimagicField {
+		t.Fatal("antimagic field not in tier 3 catalog")
+	}
+	if dmg := rollTrapDamage(anti, "any-run", 0); dmg != 0 {
+		t.Errorf("antimagic field should deal 0 damage, got %d", dmg)
+	}
+}
+
+func TestZoneTrapRoom_AntimagicFieldNoHPLoss(t *testing.T) {
+	setupAuditTestDB(t)
+	uid := id.UserID("@zone-trap-antimagic:example")
+	zoneCmdTestCharacter(t, uid, 5)
+	defer cleanupZoneRuns(uid)
+
+	run, err := startZoneRun(uid, ZoneManorBlackspire, 5, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	zone, _ := getZone(ZoneManorBlackspire)
+	dndChar, _ := LoadDnDCharacter(uid)
+	startHP := dndChar.HPCurrent
+
+	var anti zoneTrapDef
+	for _, tr := range tier3TrapCatalog {
+		if tr.Kind == TrapAntimagicField {
+			anti = tr
+			break
+		}
+	}
+
+	p := &AdventurePlugin{}
+	dmg, narration := p.applyTrapEffectWithDetect(uid, run, zone, dndChar, anti,
+		failedDetect(anti.DetectSkill, anti.DetectDC))
+	if dmg != 0 {
+		t.Errorf("antimagic field should deal 0 damage even on fail, got %d", dmg)
+	}
+	if !strings.Contains(narration, "Antimagic") {
+		t.Errorf("antimagic narration missing trap name: %q", narration)
+	}
+	c, _ := LoadDnDCharacter(uid)
+	if c.HPCurrent != startHP {
+		t.Errorf("antimagic field should not change HP: cur=%d, want=%d", c.HPCurrent, startHP)
+	}
+}
+
 func TestRollZoneLoot_BossLootDrops(t *testing.T) {
 	setupAuditTestDB(t)
 	uid := id.UserID("@zone-loot:example")

internal/plugin/dnd_zone_traps.go

@@ -27,6 +27,10 @@ const (
 	TrapFlameJet       ZoneTrapKind = "flame_jet"
 	TrapCollapsingCeil ZoneTrapKind = "collapsing_ceiling"
 	TrapGlyphOfWarding ZoneTrapKind = "glyph_of_warding"
+	TrapAntimagicField ZoneTrapKind = "antimagic_field"
+	TrapNecroticMiasma ZoneTrapKind = "necrotic_miasma"
+	TrapSymbolOfDeath  ZoneTrapKind = "symbol_of_death"
+	TrapPlanarRift     ZoneTrapKind = "planar_rift"
 )
 
 // zoneTrapDef — static definition of a zone trap. Damage dice are in
@@ -40,10 +44,11 @@ type zoneTrapDef struct {
 	DetectDC      int
 	DamageDiceN   int     // 0 if no direct damage
 	DamageDiceD   int     // sides
-	DamageType    string  // "bludgeoning", "piercing", "poison", ...
+	DamageType      string // "bludgeoning", "piercing", "poison", ...
-	AlertsEnemies bool    // tripwire-class: 0 damage, raises alarm
+	AlertsEnemies   bool   // tripwire-class: 0 damage, raises alarm
-	Tier          ZoneTier
+	SuppressesMagic bool   // antimagic-class: 0 damage, narrative suppression
-	Weight        int     // 1..10, default 5
+	Tier            ZoneTier
+	Weight          int    // 1..10, default 5
 }
 
 // tier1TrapCatalog — design doc §6 Tier 1 table.
@@ -126,14 +131,83 @@ var tier2TrapCatalog = []zoneTrapDef{
 	},
 }
 
-// trapsByTier returns all traps registered at the given tier. Tier 3+
+// tier3TrapCatalog — design doc §6 Tier 3–5 table. The doc lumps all
-// catalogs append to this switch in later sub-phases (D4a).
+// high-tier traps into a single list, so tiers 3, 4, and 5 share this
+// pool. Two of the four entries (Antimagic Field, Symbol of Death) have
+// effects that don't fit the dice-only damage model:
+//
+//   - Antimagic Field: no damage; SuppressesMagic flag flips the
+//     narration to a non-damaging suppression beat. The actual
+//     spell-suppression mechanic is left to a later phase — for now
+//     the line tells the player magic is choked in this room.
+//   - Necrotic Miasma: design doc says "6d6 + max HP -10 until long
+//     rest". The max-HP debuff isn't modeled here; trap delivers the
+//     6d6 necrotic damage only.
+//   - Symbol of Death: doc reads "INT DC 20 or drop to 0 HP". We
+//     approximate with 8d10 psychic; the existing near-KO cap in
+//     applyTrapEffectWithDetect prevents an outright kill.
+//   - Planar Rift: 4d10 psychic. The teleport-to-random-room mechanic
+//     isn't modeled — trap just deals psychic damage for now.
+var tier3TrapCatalog = []zoneTrapDef{
+	{
+		Kind:            TrapAntimagicField,
+		Display:         "Antimagic Field",
+		Trigger:         "the air thickens and every charm at your belt goes cold",
+		DetectSkill:     SkillArcana,
+		DetectDC:        18,
+		SuppressesMagic: true,
+		Tier:            ZoneTierJourneyman,
+		Weight:          3,
+	},
+	{
+		Kind:        TrapNecroticMiasma,
+		Display:     "Necrotic Miasma",
+		Trigger:     "the sarcophagus lid shifts and a green-black fume pours out",
+		DetectSkill: SkillPerception,
+		DetectDC:    16,
+		DamageDiceN: 6,
+		DamageDiceD: 6,
+		DamageType:  "necrotic",
+		Tier:        ZoneTierJourneyman,
+		Weight:      5,
+	},
+	{
+		Kind:        TrapSymbolOfDeath,
+		Display:     "Symbol of Death",
+		Trigger:     "an inscribed sigil flares and your vision blanks to white",
+		DetectSkill: SkillInvestigation,
+		DetectDC:    20,
+		DamageDiceN: 8,
+		DamageDiceD: 10,
+		DamageType:  "psychic",
+		Tier:        ZoneTierJourneyman,
+		Weight:      2,
+	},
+	{
+		Kind:        TrapPlanarRift,
+		Display:     "Planar Rift",
+		Trigger:     "the floor folds wrong and a tear of starless dark grasps at you",
+		DetectSkill: SkillArcana,
+		DetectDC:    20,
+		DamageDiceN: 4,
+		DamageDiceD: 10,
+		DamageType:  "psychic",
+		Tier:        ZoneTierJourneyman,
+		Weight:      3,
+	},
+}
+
+// trapsByTier returns all traps registered at the given tier. Tiers 3,
+// 4, and 5 share the Tier 3 catalog per the design doc's combined
+// "Tier 3–5 Traps" table; later phases may split them.
 func trapsByTier(t ZoneTier) []zoneTrapDef {
 	switch t {
 	case ZoneTierBeginner:
 		return tier1TrapCatalog
 	case ZoneTierApprentice:
 		return tier2TrapCatalog
+	case ZoneTierJourneyman, ZoneTierVeteran, ZoneTierLegendary:
+		return tier3TrapCatalog
 	}
 	return nil
 }
@@ -190,7 +264,7 @@ func zoneTrapSelectorHash(runID string, roomIdx int) uint64 {
 // here; the design-doc CON DC 11 save is folded into the same dice pool
 // as a flattened average.
 func rollTrapDamage(tr zoneTrapDef, runID string, roomIdx int) int {
-	if tr.AlertsEnemies || tr.DamageDiceN == 0 || tr.DamageDiceD == 0 {
+	if tr.AlertsEnemies || tr.SuppressesMagic || tr.DamageDiceN == 0 || tr.DamageDiceD == 0 {
 		return 0
 	}
 	rng := rand.New(rand.NewPCG(zoneTrapSelectorHash(runID, roomIdx), 0x712D2A))
@@ -207,6 +281,9 @@ func trapDamageHeader(tr zoneTrapDef, dmg int, hpCur, hpMax int) string {
 	if tr.AlertsEnemies {
 		return fmt.Sprintf("🔔 **%s** — %s. The next room knows you're here.", tr.Display, tr.Trigger)
 	}
+	if tr.SuppressesMagic {
+		return fmt.Sprintf("🚫 **%s** — %s. Spells fizzle and enchanted gear sleeps until you leave the room.", tr.Display, tr.Trigger)
+	}
 	dice := fmt.Sprintf("%dd%d", tr.DamageDiceN, tr.DamageDiceD)
 	return fmt.Sprintf("💢 **%s** (%s %s) — **%d HP** (%d/%d remaining).",
 		tr.Display, dice, tr.DamageType, dmg, hpCur, hpMax)