VScripts overview

Overview of the Lua scripting layer in Legends of Dota Redux

What are VScripts?

Dota 2 custom games use a server-side Lua scripting system called VScripts. When a custom game loads, the Dota 2 engine executes a root entry point (addon_game_mode.lua) which bootstraps every other module using Lua’s require function or Valve’s LinkLuaModifier helper for modifier classes.

All scripts live under:

game/scripts/vscripts/

Modifiers (passive buff/debuff classes) must be registered before use:

LinkLuaModifier(
    "modifier_neutral_power",
    "abilities/modifiers/modifier_neutral_power.lua",
    LUA_MODIFIER_MOTION_NONE
)

Regular modules are loaded with require:

local constants = require('constants')
require('lib/timers')

Script file reference

File	Purpose
addon_game_mode.lua	Root entry point; wires up all game-mode events
pregame.lua	Hero/skill selection phase — the most important file in Redux
ingame.lua	Gameplay systems: respawning, gold balancing, towers, mutators
commands.lua	All player-typed chat commands (vote, debug, and cheat commands)
optionmanager.lua	Shared key–value store for game options
util.lua	General-purpose utilities used across all other modules
constants.lua	Hardcoded numeric constants shared across the project
network.lua	Network table helpers for syncing state to clients
chat.lua	Custom chat system used during the menu/lobby phase
skillmanager.lua	Functions for swapping hero skills mid-game
spellfixes.lua	Per-ability corrections, fixes, and balance patches
dedicated.lua	Dedicated-server configuration helpers
lod_debug.lua	Console commands for server-side debugging
optionmanager.lua	Game option accessors (GetOption / SetOption)
panorama_shop.lua	Layout and logic for the custom Panorama shop (from Angel Arena: Black Star)
obstacles.lua	Obstacle spawn list for the deprecated Duel arena mechanic
survival.lua	Incomplete co-op holdout game mode (Ash47)
challenge.lua	Incomplete co-op holdout variant (Ash47)
triggers.lua	Map trigger handlers
stats_client.lua	Client-side statistics collection

Directory structure

vscripts/
├── addon_game_mode.lua
├── pregame.lua
├── ingame.lua
├── commands.lua
├── optionmanager.lua
├── util.lua
├── constants.lua
├── network.lua
├── chat.lua
├── skillmanager.lua
├── spellfixes.lua
├── lod_debug.lua
├── panorama_shop.lua
├── abilities/
│   ├── modifiers/
│   ├── mutators/
│   ├── global_mutators/
│   ├── hero_perks/
│   └── ...
├── lib/
│   ├── timers.lua
│   ├── wearables.lua
│   └── StatUploaderFunctions.lua
└── statcollection/
    └── init.lua

How scripts are loaded

pregame.lua is the main bootstrap file. It requires every other core module and calls LinkLuaModifier for every Lua-based modifier that the game needs:

-- Standard module requires
local constants = require('constants')
local SpellFixes = require('spellfixes')
require('lib/timers')
require('chat')
require('dedicated')

-- Modifier registration (must happen before any unit with that modifier is spawned)
LinkLuaModifier(
    "modifier_vampirism_mutator",
    "abilities/mutators/modifier_vampirism_mutator.lua",
    LUA_MODIFIER_MOTION_NONE
)

After all requires, pregame.lua loads the game’s KV (key-value) data into GameRules.KVs:

GameRules.KVs = {}
GameRules.KVs["npc_abilities"]         = util.abilityKVs
GameRules.KVs["npc_abilities_custom"]  = LoadKeyValues('scripts/npc/npc_abilities_custom.txt')
GameRules.KVs["npc_abilities_override"]= LoadKeyValues('scripts/npc/npc_abilities_override.txt')
GameRules.KVs.herolist                 = LoadKeyValues('scripts/npc/herolist.txt')
GameRules.KVs.abilitylist             = LoadKeyValues('scripts/kv/abilities.kv')