feat: extend abilities with tryHeal and tryRally

src/abilities.lua

@@ -151,3 +151,113 @@ local function tryShriek(game, monster)
   return true, string.format("%s's wail blinds you", monster.name)
 end
 
+-- Cleric-style ability: mends the neediest hurt ally within range and line of
+-- sight instead of attacking. Ties break on the lowest hp fraction. Filtered
+-- to other.kind == "monster" - the same "hostile" tag every other module
+-- (companions.lua/mercenaries.lua/reanimation.lua's own nearestHostile,
+-- commands.lua's isVisibleHostile) already keys off of - so a dark cleric
+-- mends a fellow monster, never the player's own wounded companion, hireling
+-- or thrall sharing the same entities list.
+local function tryHeal(game, monster)
+  local best, bestRatio = nil, 1
+  for _, other in ipairs(game.level.entities) do
+    if other ~= monster and other.kind == "monster" and other:isAlive() and other.hp < other.maxHp then
+      local dist = math.max(math.abs(other.x - monster.x), math.abs(other.y - monster.y))
+      if dist <= RANGE.heal and Los.clear(game.level.map, monster.x, monster.y, other.x, other.y) then
+        local ratio = other.hp / other.maxHp
+        if ratio < bestRatio then bestRatio, best = ratio, other end
+      end
+    end
+  end
+  if not best then return false end
+  local amount = 6
+  local before = best.hp
+  best.hp = math.min(best.maxHp, best.hp + amount)
+  monster.cooldown = COOLDOWN.heal
+  return true, string.format("%s mends %s for %d", monster.name, best.name, best.hp - before)
+end
+
+-- Chieftain-style ability: grants every adjacent, not-yet-buffed ally (and
+-- itself) a temporary attack boost. No-op once the whole knot is already lit.
+-- Filtered to other.kind == "monster" for the same reason tryHeal above is:
+-- without it a chieftain standing next to the player's companion, hireling
+-- or thrall would rally that ally of the PLAYER's instead of one of its own.
+local function tryRally(game, monster)
+  local buffed = {}
+  for _, other in ipairs(game.level.entities) do
+    if other ~= monster and other.kind == "monster" and other:isAlive() and not Status.has(other, Status.STRENGTH)
+      and math.abs(other.x - monster.x) <= 1 and math.abs(other.y - monster.y) <= 1 then
+      Status.apply(other, Status.STRENGTH, 10, 2)
+      buffed[#buffed + 1] = other.name
+    end
+  end
+  if #buffed == 0 then return false end
+  Status.apply(monster, Status.STRENGTH, 10, 2)
+  monster.cooldown = COOLDOWN.rally
+  return true, string.format("%s rallies %s", monster.name, table.concat(buffed, ", "))
+end
+
+-- Footpad-style ability: not cooldown-gated. Once adjacent it lifts a single
+-- non-essential item (never an equipped key or the amulet, since those never
+-- sit unequipped in inventory) and flees for the rest of the encounter; a
+-- fleeing footpad just keeps running rather than trying again.
+local function trySteal(game, monster)
+  if monster.fleeing then
+    game:stepMonsterAway(monster, game.player.x, game.player.y)
+    return true
+  end
+  if not game:playerAdjacent(monster) then return false end
+  local idx = game:findInInventory(function(item)
+    return item.kind ~= Items.KEY and item.kind ~= Items.AMULET
+  end)
+  if not idx then
+    monster.fleeing = true
+    return true, string.format("%s finds nothing worth stealing and flees", monster.name)
+  end
+  local item = table.remove(game.player.inventory, idx)
+  monster.stolen = item
+  monster.fleeing = true
+  return true, string.format("%s steals your %s and flees", monster.name, item.name)
+end
+
+local dispatch = { summon = trySummon, curse = tryCurse, heal = tryHeal, rally = tryRally, shriek = tryShriek }
+
+-- Called once per monster turn, after status ticks and regen but before
+-- ai.lua. Returns true when the ability consumed the turn.
+function Abilities.tryAct(game, monster)
+  if not monster.ability then return false end
+  if monster.ability == "steal" then
+    local acted, line = trySteal(game, monster)
+    if acted and line then game.log:add(line) end
+    return acted == true
+  end
+  local handler = dispatch[monster.ability]
+  if not handler or (monster.cooldown and monster.cooldown > 0) then return false end
+  local acted, line = handler(game, monster)
+  if not acted then return false end
+  if line then game.log:add(line) end
+  return true
+end
+
+-- Slime-style reaction: fired from Game:playerAttack when a hit lands but
+-- does not kill. Halves the victim's max hp and spawns a clone at the other
+-- half, capped at two splits total (`splitGen`) so a slime cannot be farmed
+-- into an unbounded swarm.
+function Abilities.onHit(game, target)
+  if target.ability ~= "split" then return nil end
+  if not target:isAlive() or target.maxHp < 4 then return nil end
+  if (target.splitGen or 0) >= 2 then return nil end
+  local x, y = freeAdjacent(game, target.x, target.y)
+  if not x then return nil end
+  local newMax = target.maxHp // 2
+  target.maxHp = newMax
+  target.hp = math.min(target.hp, newMax)
+  target.splitGen = (target.splitGen or 0) + 1
+  local clone = game:spawnMinion(target.species, x, y)
+  clone.maxHp = newMax
+  clone.hp = newMax
+  clone.splitGen = target.splitGen
+  return string.format("the %s splits in two", target.name)
+end
+
+return Abilities

src/affixes.lua

@@ -1,14 +1,18 @@
 -- Gear affixes. A weapon or armour piece may roll a prefix that bumps its power
 -- and, for some weapons, attaches an on-hit rider (e.g. flaming sets the target
 -- alight). Rolls draw from the shared rng so drops stay deterministic per seed.
+-- An elemental rider also retags the weapon's own base swing (damageType,
+-- read by combat.lua) to match - a flaming sword fights with fire, not steel,
+-- so it hits harder against a cold-weak target and can do nothing at all
+-- against something fire-immune.
 
 local Affixes = {}
 
 Affixes.weapon = {
   { key = "sharp",   name = "sharp",   power = 1 },
   { key = "vicious", name = "vicious", power = 2 },
-  { key = "flaming", name = "flaming", power = 1, onHit = { status = "burning", duration = 3, potency = 2 } },
-  { key = "venomed", name = "venomed", power = 0, onHit = { status = "poison",  duration = 4, potency = 1 } },
+  { key = "flaming", name = "flaming", power = 1, onHit = { status = "burning", duration = 3, potency = 2 }, damageType = "fire" },
+  { key = "venomed", name = "venomed", power = 0, onHit = { status = "poison",  duration = 4, potency = 1 }, damageType = "poison" },
 }
 
 Affixes.armor = {
@@ -31,9 +35,10 @@ end
 
 function Affixes.decorate(item, affix)
   if not affix then return item end
-  item.affix = { key = affix.key, name = affix.name, power = affix.power, onHit = affix.onHit }
+  item.affix = { key = affix.key, name = affix.name, power = affix.power, onHit = affix.onHit, damageType = affix.damageType }
   item.power = item.power + affix.power
   item.name = affix.name .. " " .. item.name
+  item.damageType = affix.damageType
   return item
 end
 

src/ai.lua

@@ -2,15 +2,38 @@
 -- resolves that monster's turn through game helpers, so all state mutation and
 -- rng use stays centralised and deterministic.
 
+local Status = require("status")
+local Infighting = require("infighting")
+
 local Ai = {}
 
-local AGGRO = { chase = 10, pack = 13, ranged = 12, flee = 8, erratic = 8 }
+local AGGRO = { chase = 10, pack = 13, ranged = 12, flee = 8, erratic = 8, tunnel = 10 }
 local DIRS = { { 1, 0 }, { -1, 0 }, { 0, 1 }, { 0, -1 } }
 
+-- A player-aligned ally standing adjacent to `monster` occupies its cell
+-- exactly the way a wall would for Game:stepMonsterToward's own pathfinding
+-- (blockedForMonster treats any occupied non-goal cell as impassable) - so a
+-- one-wide corridor an ally is plugging leaves every pursuit behaviour below
+-- with no route at all, and without this check they simply idle beside it
+-- forever rather than fighting the living combatant in their way. Resolves
+-- through Infighting.strike, the same generic monster-vs-any-creature combat
+-- infighting.lua already uses for rivalries and discord. Returns true once
+-- it has spent the monster's turn this way, so each caller can bail out at
+-- the same priority Game:playerAdjacent already has over closing distance.
+local function attackBlockingAlly(game, monster)
+  local ally = game:adjacentAlly(monster)
+  if not ally then return false end
+  Infighting.strike(game, monster, ally)
+  return true
+end
+
 local function chase(game, monster)
   if game:playerAdjacent(monster) then
     game:monsterMelee(monster)
-  elseif game:canSeePlayer(monster, AGGRO.chase) then
+    return
+  end
+  if attackBlockingAlly(game, monster) then return end
+  if game:canSeePlayer(monster, AGGRO.chase) then
     game:stepMonsterToward(monster, game.player.x, game.player.y)
   end
 end
@@ -20,6 +43,7 @@ local function pack(game, monster)
     game:monsterMelee(monster)
     return
   end
+  if attackBlockingAlly(game, monster) then return end
   if game:canSeePlayer(monster, AGGRO.pack) then
     game:stepMonsterToward(monster, game.player.x, game.player.y)
     return
@@ -39,6 +63,7 @@ local function ranged(game, monster)
     end
     return
   end
+  if attackBlockingAlly(game, monster) then return end
   if game:canSeePlayer(monster, AGGRO.ranged) then
     game:stepMonsterToward(monster, game.player.x, game.player.y)
   end
@@ -50,6 +75,14 @@ local function flee(game, monster)
   end
 end
 
+-- Shopkeepers idle unless game.lua has already flagged them hostile (a theft
+-- from their stock), at which point they behave exactly like a chaser.
+local function vend(game, monster)
+  if monster.hostile then
+    chase(game, monster)
+  end
+end
+
 local function erratic(game, monster)
   if game:playerAdjacent(monster) then
     game:monsterMelee(monster)
@@ -63,15 +96,45 @@ local function erratic(game, monster)
   end
 end
 
+-- A burrower: melee once adjacent, chase like anything else once it can see
+-- the player through open floor, otherwise claw straight through whatever
+-- rock stands between them (see Game:monsterDig, digging.lua) rather than
+-- idling the way a plain chaser out of sight would.
+local function tunnel(game, monster)
+  if game:playerAdjacent(monster) then
+    game:monsterMelee(monster)
+    return
+  end
+  if attackBlockingAlly(game, monster) then return end
+  if game:canSeePlayer(monster, AGGRO.tunnel) then
+    game:stepMonsterToward(monster, game.player.x, game.player.y)
+    return
+  end
+  game:monsterDig(monster, game.player.x, game.player.y)
+end
+
 Ai.behaviours = {
   chase = chase,
   pack = pack,
   ranged = ranged,
   flee = flee,
   erratic = erratic,
+  vend = vend,
+  tunnel = tunnel,
 }
 
+-- A confused monster gets the exact same chance each turn to have its own
+-- chosen direction overridden that Game:movePlayer rolls for the player - see
+-- status.lua's Status.CONFUSE_NUMERATOR/DENOMINATOR, shared by both sides so
+-- neither one confuses more reliably than the other. On a lucky roll (or once
+-- confusion wears off) `behaviour` below runs completely untouched.
 function Ai.act(game, monster)
+  if Status.has(monster, Status.CONFUSE)
+    and game.rng:chance(Status.CONFUSE_NUMERATOR, Status.CONFUSE_DENOMINATOR) then
+    local dir = DIRS[game.rng:range(1, #DIRS)]
+    game:moveMonster(monster, dir[1], dir[2])
+    return
+  end
   local behaviour = Ai.behaviours[monster.ai] or chase
   behaviour(game, monster)
 end