Table of Contents
Creating Custom Items with JSON and Lua
This guide shows how to create completely new items in Remixed Dungeon without any Java coding. You'll learn to use JSON configuration and Lua scripting to define new weapons, armor, potions, scrolls, and special items.
Item Basics
Every item in Remixed Dungeon is defined by:
- A JSON file that describes its properties
- Optional Lua scripts that define special behaviors
- An image file for its sprite
Simple Item: Custom Weapon
Step 1: Create the Item JSON
Create items/weapon/custom_sword.json:
{
"class": "com.watabou.pixeldungeon.items.weapon.melee.MeleeWeapon",
"name:en": "Lightning Sword",
"name:ru": "Меч молнии",
"desc:en": "This sword crackles with electrical energy that jumps to nearby enemies.",
"desc:ru": "Этот меч искрится электрической энергией, перекачивающейся на ближайших врагов.",
"imageIndex": 15,
"damageMin": 6,
"damageMax": 12,
"AC": "ATTACK",
"Tier": 3,
"script": "items/lightning_sword.lua",
"onHit": "lightningStrike",
"onEquip": "equipEffect",
"onUnequip": "unequipEffect"
}
Step 2: Create the Lua Script
Create items/lightning_sword.lua:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 15, imageFile = "items.png", name = "Lightning Sword", info = "This sword crackles with electrical energy that jumps to nearby enemies.", stackable = false, upgradable = true, isFlies = false, defaultAction = "ATTACK" } end, -- Called when the weapon hits an enemy attackProc = function(self, cell, enemy, hero, damage) -- Find nearby enemies (within 2 tiles) using level mobs local mobs = RPD.Dungeon.level():mobs() for i = 0, mobs:size()-1 do local mob = mobs:get(i) if mob ~= enemy and RPD.Dungeon.level():distance(enemy:getPos(), mob:getPos()) <= 2 then local lightningDamage = math.random(1, 5) -- Apply some damage (actual calculation would be more complex) mob:damage(lightningDamage, hero) -- Damage mob, source is hero RPD.glog("Lightning arcs to " .. mob:name() .. "!") end end -- Show visual effect (using available effect) RPD.topEffect(enemy:getPos(), "electrical") return damage end, activate = function(self, item, hero) -- Called when item is equipped RPD.glog("Electricity surges through your body!") end, deactivate = function(self, item, hero) -- Called when item is unequipped RPD.glog("The electrical sensation fades.") end }
Step 3: Add the Sprite
Add your custom sword sprite to sprites/items/weapon.png at index 15 (the location specified in imageIndex).
Custom Potion Example
JSON Definition
Create items/potions/custom_potion.json:
{
"class": "com.watabou.pixeldungeon.items.potions.Potion",
"name:en": "Potion of Phase Shift",
"name:ru": "Зелье фазового сдвига",
"desc:en": "Drinking this potion will make you temporarily phase through walls and enemies for a short time.",
"desc:ru": "Выпив это зелье, вы временно будете проходить сквозь стены и врагов в течение короткого времени.",
"imageIndex": 22,
"script": "items/potion_phase.lua",
"onDrink": "phaseShift"
}
Lua Script
Create items/potion_phase.lua:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 22, imageFile = "items.png", name = "Potion of Phase Shift", info = "Drinking this potion will make you temporarily phase through walls and enemies for a short time.", stackable = true, upgradable = false, isFlies = false, defaultAction = "DRINK" } end, actions = function() return {RPD.Actions.DRINK} end, execute = function(self, item, hero, action) if action == RPD.Actions.DRINK then RPD.glog("You feel insubstantial!") -- Apply phase buff for 10 turns using RPD API RPD.affectBuff(hero, RPD.Buffs.Invisibility, 10) -- Using invisibility as example buff -- Show visual effect (using available effect) RPD.topEffect(hero:getPos(), "wind") end end }
Buff Definition
Create the buff that enables phasing in buffs/phase_buff.json:
{
"class": "com.watabou.pixeldungeon.actors.buffs.Buff",
"name:en": "Phase",
"desc:en": "You can move through walls and enemies.\nDuration: %d turns",
"imageIndex": 25,
"script": "buffs/phase_buff.lua",
"onAdd": "startPhase",
"onRemove": "endPhase",
"onStep": "onStep"
}
And the Lua script buffs/phase_buff.lua:
local RPD = require "scripts/lib/commonClasses" local buff = require "scripts/lib/buff" return buff.init{ desc = function() return { icon = 25, name = "Phase", info = "You can move through walls and enemies.\\nDuration: %d turns" } end, attach = function(self, target) -- Called when buff is applied self.target = target RPD.glog("You phase out of reality!") return true end, act = function(self) -- Called each turn while active -- Visual effect each step RPD.topEffect(self.target:getPos(), "step") -- Continue for another turn return true end, detach = function(self) -- Called when buff is removed RPD.glog("You phase back into reality.") end }
Custom Scroll Example
JSON Definition
Create items/scrolls/custom_scroll.json:
{
"class": "com.watabou.pixeldungeon.items.scrolls.Scroll",
"name:en": "Scroll of Telepathy",
"name:ru": "Свиток телепатии",
"desc:en": "Reading this scroll will allow you to sense the minds of all creatures for a time, revealing their location and basic information.",
"desc:ru": "Прочтение этого свитка позволит вам ощущать разум всех существ некоторое время, раскрывая их местоположение и базовую информацию.",
"imageIndex": 12,
"script": "items/scroll_telepathy.lua",
"onRead": "activateTelepathy"
}
Lua Script
Create items/scroll_telepathy.lua:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 12, imageFile = "items.png", name = "Scroll of Telepathy", info = "Reading this scroll will allow you to sense the minds of all creatures for a time, revealing their location and basic information.", stackable = true, upgradable = false, isFlies = false, defaultAction = "READ" } end, actions = function() return {RPD.Actions.READ} end, execute = function(self, scroll, hero, action) if action == RPD.Actions.READ then RPD.glog("You can feel the minds of all creatures!") -- Apply telepathy buff for 20 turns RPD.affectBuff(hero, RPD.Buffs.MindVision, 20) -- Using MindVision as example buff -- Show visual effect RPD.topEffect(hero:getPos(), "telepathy") end end }
Telepathy Buff
Create buffs/telepathy_buff.json:
{
"class": "com.watabou.pixeldungeon.actors.buffs.Buff",
"name:en": "Telepathy",
"desc:en": "You can sense the minds of all creatures.\nDuration: %d turns",
"imageIndex": 26,
"script": "buffs/telepathy_buff.lua",
"onAdd": "startTelepathy",
"onRemove": "endTelepathy",
"onTurn": "updateTelepathy"
}
And buffs/telepathy_buff.lua:
local RPD = require "scripts/lib/commonClasses" local M = {} function M.startTelepathy(buff, target) RPD.glog("You can sense minds throughout the dungeon!") end function M.endTelepathy(buff, target) RPD.glog("The mental noise fades.") end function M.updateTelepathy(buff, target) -- Reveal all creatures on the level every few turns -- Note: This effect would depend on specific game mechanics - this is conceptual local level = RPD.Dungeon.level() local mobs = level:mobs() for i = 0, mobs:size()-1 do local mob = mobs:get(i) -- Reveal 1 tile around mob (conceptual implementation) end end return M
Custom Armor Example
JSON Definition
Create items/armor/custom_armor.json:
{
"class": "com.watabou.pixeldungeon.items.armor.Armor",
"name:en": "Shielding Armor",
"name:ru": "Экранирующая броня",
"desc:en": "This armor glows with a protective field that sometimes blocks attacks completely.",
"desc:ru": "Эта броня светится защитным полем, которое иногда полностью блокирует атаки.",
"imageIndex": 8,
"AC": "EQUIP",
"Tier": 4,
"baseDefenseFactor": 12,
"script": "items/armor_shielding.lua",
"onHit": "tryBlock",
"onEquip": "equipEffect"
}
Lua Script
Create items/armor_shielding.lua:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 8, imageFile = "items.png", name = "Shielding Armor", info = "This armor glows with a protective field that sometimes blocks attacks completely.", stackable = false, upgradable = true, isFlies = false, defaultAction = "EQUIP" } end, defenceProc = function(self, enemy, damage) -- 25% chance to completely block the attack if math.random() < 0.25 then -- 25% chance RPD.glog("Your armor's shield blocks the attack!") RPD.topEffect(self:getOwner():getPos(), "shield") -- Use available effect return 0 -- Reduce damage to 0 end return damage -- Return original damage if not blocked end, activate = function(self, item, hero) RPD.glog("A protective field envelops you.") end }
Advanced Item Techniques
Item Sets
Create items that work together:
{
"class": "com.watabou.pixeldungeon.items.weapon.melee.Sword",
"name:en": "Sword of Elements",
"set": "elemental_weapons",
"enchantments": ["fire", "ice", "shock"],
"script": "items/elemental_sword.lua",
"onHit": "applyElement"
}
Conditional Behavior
Use Lua to create context-sensitive items:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 0, imageFile = "items.png", name = "Conditional Item", info = "An item with context-sensitive effects.", stackable = false, upgradable = true, isFlies = false, defaultAction = "USE" } end, actions = function() return {RPD.Actions.USE} end, execute = function(self, item, hero, action) if action == RPD.Actions.USE then local level = RPD.Dungeon.level() local heroHP = hero:getHP() local heroMaxHP = hero:getMaxHP() if level:getDepth() < 5 then -- Stronger effect on early levels hero:heal(10, item) -- Heal hero, source is item RPD.glog("The item glows brighter in the early dungeon!") elseif heroHP < heroMaxHP * 0.3 then -- Emergency healing when low on health hero:heal(15, item) -- Heal hero, source is item RPD.glog("Desperation triggers the item's power!") else -- Normal effect hero:heal(5, item) -- Heal hero, source is item end end end }
Complex Interactions
Create items that interact with the environment:
local RPD = require "scripts/lib/commonClasses" local item = require "scripts/lib/item" return item.init{ desc = function() return { image = 0, imageFile = "items.png", name = "Environment Item", info = "An item that interacts with the environment.", stackable = false, upgradable = false, isFlies = true, defaultAction = "THROW" } end, onThrow = function(self, cell, user) local level = RPD.Dungeon.level() local terrainType = level:cell(cell) if terrainType == RPD.Terrain.WATER then -- Create a temporary bridge level:set(cell, RPD.Terrain.EMPTY) RPD.glog("The water parts before you!") elseif terrainType == RPD.Terrain.CHASM then -- Fill the chasm level:set(cell, RPD.Terrain.EMPTY) RPD.glog("A bridge of crystal forms!") end end }
Testing Your Items
Common Testing Steps
- Enable your mod in-game
- Start a new game (not a saved game) to see new items
- Verify that sprites appear correctly
- Test all item functions and Lua scripts
- Check that item descriptions are properly localized
- Confirm that item balancing is appropriate
Debugging Tips
- Check the game log for Lua errors
- Verify file paths match the expected directory structure
- Ensure JSON syntax is valid
- Make sure image indices correspond to actual sprite locations
Creating custom items without Java is quite powerful in Remixed Dungeon. With JSON and Lua, you can create complex interactions, unique mechanics, and engaging new content for players to discover!
