fix(monsters): eliminate unwired columns, dead logic, and wire elite modifier scaling

- Support up to mon25 columns in monsterColumns stopping if column does not exist
- Weight normal pack type selection by kind.rarity in planMonsterGroups
- Wire mechanical stat scaling for stoneskin, cursed, coldenchant, fireenchant, lightenchant, spectralhit, teleport, magicresistant, and aura in applyEliteModifiers
- Add unit tests for monsterColumns, rarity-weighted pack planning, and elite modifier stat scaling

TAG=agy
CONV=2a1934de-30ef-464e-b3f3-fcbcdbbc49f1

src/game/monsters.ts

@@ -605,10 +605,12 @@ export interface LevelMonsterPlan {
  * @param prefix - `mon`, `nmon` or `umon`.
  * @returns the non-empty entries, in column order.
  */
-function monsterColumns(table: D2Table, row: readonly string[], prefix: string): string[] {
+export function monsterColumns(table: D2Table, row: readonly string[], prefix: string): string[] {
   const out: string[] = []
-  for (let slot = 1; slot <= 10; slot += 1) {
-    const value = cell(table, row, `${prefix}${String(slot)}`).trim()
+  for (let slot = 1; slot <= 25; slot += 1) {
+    const col = `${prefix}${String(slot)}`
+    if (!table.header.includes(col)) break
+    const value = cell(table, row, col).trim()
     if (value !== '') out.push(value)
   }
   return out
@@ -851,6 +853,7 @@ export function applyEliteModifiers(
   modifiers: readonly string[] = [],
   superUniqueId?: string,
 ): MonsterStats {
+  let hp = base.hp
   let damage = base.damage
   let speed = base.speed
   if (modifiers.includes('strong')) {
@@ -859,8 +862,37 @@ export function applyEliteModifiers(
   if (modifiers.includes('fast')) {
     speed = Math.round(speed * 1.4 * 100) / 100
   }
+  if (modifiers.includes('stoneskin')) {
+    hp = Math.round(hp * 2)
+  }
+  if (modifiers.includes('cursed')) {
+    damage = Math.round(damage * 1.2)
+  }
+  if (modifiers.includes('coldenchant')) {
+    damage = Math.round(damage * 1.2)
+  }
+  if (modifiers.includes('fireenchant')) {
+    damage = Math.round(damage * 1.2)
+  }
+  if (modifiers.includes('lightenchant')) {
+    damage = Math.round(damage * 1.2)
+  }
+  if (modifiers.includes('spectralhit')) {
+    damage = Math.round(damage * 1.2)
+  }
+  if (modifiers.includes('teleport')) {
+    speed = Math.round(speed * 1.2 * 100) / 100
+  }
+  if (modifiers.includes('magicresistant')) {
+    hp = Math.round(hp * 1.2)
+  }
+  if (modifiers.includes('aura')) {
+    damage = Math.round(damage * 1.2)
+    speed = Math.round(speed * 1.1 * 100) / 100
+  }
   return {
     ...base,
+    hp,
     damage,
     speed,
     rank,
@@ -994,8 +1026,17 @@ export function planMonsterGroups(
     remaining -= count
   }
 
+  const totalRarity = types.reduce((sum, kind) => sum + Math.max(1, kind.rarity), 0)
   while (remaining > 0) {
-    const kind = types[rng.int(0, types.length - 1)]!
+    let ticket = rng.next() * totalRarity
+    let kind = types[types.length - 1]!
+    for (let j = 0; j < types.length; j += 1) {
+      ticket -= Math.max(1, types[j]!.rarity)
+      if (ticket <= 0) {
+        kind = types[j]!
+        break
+      }
+    }
     const count = Math.min(remaining, Math.max(1, rng.int(kind.minGroup, kind.maxGroup)))
     groups.push({ kind, count, rank: 'normal' })
     remaining -= count

tests/monsters.test.ts

@@ -29,6 +29,8 @@ import {
   readMonsterScaling,
   readSuperUniques,
   selectLevelTypes,
+  applyEliteModifiers,
+  monsterColumns,
   UNSCALED,
 } from '../src/game/monsters.ts'
 import type { MonsterKind } from '../src/game/monsters.ts'
@@ -477,6 +479,22 @@ describe('planMonsterGroups', () => {
     expect(planMonsterGroups(plan, types, kinds, 0, new Rng(1))).toEqual([])
     expect(planMonsterGroups(plan, [], kinds, 10, new Rng(1))).toEqual([])
   })
+
+  it('weights normal pack type selection using kind.rarity', () => {
+    const rareKind: MonsterKind = { ...types[0]!, id: 'rare', rarity: 1, minGroup: 1, maxGroup: 1 }
+    const commonKind: MonsterKind = { ...types[0]!, id: 'common', rarity: 100, minGroup: 1, maxGroup: 1 }
+    const customTypes = [rareKind, commonKind]
+    const customPlan = { ...plan, eliteMin: 0, eliteMax: 0 }
+    let commonCount = 0
+    let rareCount = 0
+    const rng = new Rng(42)
+    for (let i = 0; i < 200; i += 1) {
+      const groups = planMonsterGroups(customPlan, customTypes, kinds, 1, rng)
+      if (groups[0]?.kind.id === 'common') commonCount += 1
+      if (groups[0]?.kind.id === 'rare') rareCount += 1
+    }
+    expect(commonCount).toBeGreaterThan(rareCount * 10)
+  })
 })
 
 describe('monsterStatsOf', () => {
@@ -783,3 +801,66 @@ describe('monsterStatsOf with MonLvl scaling', () => {
     expect(withLevel50.xp).toBeGreaterThan(scaledNormal.xp * 20)
   })
 })
+
+describe('monsterColumns', () => {
+  it('reads columns up to slot 25 and stops when column is missing in header', () => {
+    const header = ['Id', 'mon1', 'mon2', 'mon3', 'mon4', 'mon5']
+    const row = ['1', 'fallen', 'zombie', '', 'skeleton', '']
+    const cols = monsterColumns({ header, rows: [row] }, row, 'mon')
+    expect(cols).toEqual(['fallen', 'zombie', 'skeleton'])
+  })
+
+  it('supports up to mon25 when present in header', () => {
+    const header = ['Id', ...Array.from({ length: 25 }, (_, i) => `mon${String(i + 1)}`)]
+    const row = ['1', ...Array.from({ length: 25 }, (_, i) => (i === 24 ? 'hellbovine' : ''))]
+    const cols = monsterColumns({ header, rows: [row] }, row, 'mon')
+    expect(cols).toEqual(['hellbovine'])
+  })
+})
+
+describe('applyEliteModifiers stat scaling', () => {
+  const baseStats = {
+    id: 'zombie',
+    name: 'Zombie',
+    hp: 100,
+    damage: 10,
+    speed: 10,
+    reach: 40,
+    aggroRadius: 200,
+    cooldownTicks: 25,
+    xp: 50,
+  }
+
+  it('applies stoneskin hp scaling (2x)', () => {
+    const res = applyEliteModifiers(baseStats, 'unique', ['stoneskin'])
+    expect(res.hp).toBe(200)
+  })
+
+  it('applies cursed damage scaling (1.2x)', () => {
+    const res = applyEliteModifiers(baseStats, 'unique', ['cursed'])
+    expect(res.damage).toBe(12)
+  })
+
+  it('applies elemental and spectralhit damage scaling (1.2x)', () => {
+    expect(applyEliteModifiers(baseStats, 'unique', ['coldenchant']).damage).toBe(12)
+    expect(applyEliteModifiers(baseStats, 'unique', ['fireenchant']).damage).toBe(12)
+    expect(applyEliteModifiers(baseStats, 'unique', ['lightenchant']).damage).toBe(12)
+    expect(applyEliteModifiers(baseStats, 'unique', ['spectralhit']).damage).toBe(12)
+  })
+
+  it('applies teleport speed scaling (1.2x)', () => {
+    const res = applyEliteModifiers(baseStats, 'unique', ['teleport'])
+    expect(res.speed).toBe(12)
+  })
+
+  it('applies magicresistant hp scaling (1.2x)', () => {
+    const res = applyEliteModifiers(baseStats, 'unique', ['magicresistant'])
+    expect(res.hp).toBe(120)
+  })
+
+  it('applies aura damage (1.2x) and speed (1.1x) scaling', () => {
+    const res = applyEliteModifiers(baseStats, 'unique', ['aura'])
+    expect(res.damage).toBe(12)
+    expect(res.speed).toBe(11)
+  })
+})