[vscript] Minecraft-style command system for L4D2

Bring Minecraft-style commands to Left 4 Dead 2! This addon introduces a chat-based command system inspired by Minecraft Java Edition (1.16.5–1.21.1), allowing you to control entities, spawn items, teleport players, modify attributes, and more directly through the chat box. Simply type "/" followed by a command to execute it!

Supported Commands

• /kill — Kill or remove selected entities.
• /damage — Deal damage with configurable damage types.
• /summon — Spawn infected, items, props, and custom entities.
• /give — Give weapons or items to survivors.
• /clear — Remove items from survivors' inventories.
• /replaceitem — Replace items in specific inventory slots.
• /effect — Apply or remove status effects.
• /function — Execute built-in functions or functions registered by other VScript addons.
• /gamemode — Change a player's damage protection mode.
• /tp — Teleport entities to coordinates or other entities.
• /attribute — Read, modify, or remove ConVars, NetProps, and ScriptScope attributes.

Additional utility commands:

• /mcstatus — Display command system status and diagnostic information.
• /mcselect — Inspect entities matched by a target selector.

Command Syntax

Most commands follow the syntax of Minecraft Java Edition, so their basic usage will not be repeated here.

Minecraft command reference: Minecraft Wiki — Commands

Target selector reference: Minecraft Wiki — Target Selectors

However, several commands and selectors have been modified or extended to accommodate L4D2's Source engine.

1. Coordinate System

Minecraft uses the Y-axis for vertical height, while Source uses the Z-axis.

Therefore, this addon follows L4D2's native coordinate system:

• X — Horizontal position
• Y — Horizontal position
• Z — Vertical height

Relative coordinates (~) are supported.

Additionally, compact relative coordinates are supported, allowing "~ ~ ~" to be written as "~~~".

Examples:

/tp @s ~ ~ ~100 /tp @s ~~~ /tp @s ~100~200~ /summon tank ~ ~ ~200

All distance-related parameters use Source engine units (u).

2. Target Selectors

Supported target selectors:

• @s — The command executor.
• @a — All player entities, including survivors and Special Infected.
• @e — All entities.
• @p — The nearest player entity.
• @j — The nearest eligible entity other than the executor.

You can also specify players directly by their names without using a selector.

Supported selector arguments:

• r — Maximum distance.
• rm — Minimum distance.
• name — Entity or player name.
• type — Entity type or classname.
• x, y, z — Selector origin coordinates.
• dx, dy, dz — Selection volume dimensions.
• m — Custom gamemode.
• hasitem — Checks whether an entity carries a specified item.
• has_property — Checks a ScriptScope property and its value.
• limit/c --- Quantity.

The "!" operator can be used to invert supported selector conditions.

Examples:

/kill @e[type=infected,r=1000] /kill @e[type=!survivor] /damage @e[type=tank] 100 /give @a[r=500] weapon_rifle /tp Nick @s

Note: In L4D2, Special Infected are also player entities. Therefore, type=!player excludes Special Infected as well. Use type=!survivor if you only want to exclude survivors.

For safety, /kill will not directly remove protected map entities or equipped weapons.

3. Damage Types

Unlike Minecraft, L4D2 uses Source engine damage types.

The /damage command supports Source damage flags, including bullet, slash, burn, blast, fall, crush, shock, poison, and others.

Multiple damage types can be combined using "|".

Example:

/damage @e[type=tank] 100 bullet|burn

Actual damage may still be affected by the game's damage mechanics or other addons.

4. Items and Inventory

The /give, /clear, and /replaceitem commands have been adapted to L4D2's inventory system.

Items use L4D2 weapon and entity names, such as weapon_rifle, weapon_rifle_ak47, and weapon_first_aid_kit.

Unlike Minecraft, L4D2 does not support ordinary item stacking. Giving multiple items will attempt to perform multiple inventory operations rather than create a stack.

The /replaceitem command supports L4D2's five inventory slots:

• 0 — Primary weapon
• 1 — Secondary weapon
• 2 — Throwable
• 3 — Medical item
• 4 — Pills / adrenaline

The Minecraft-style /item replace syntax is also supported as an alternative.

5. Custom Effects

The /effect command currently supports two L4D2-specific effects:

• adrenaline — Grants the adrenaline effect, with configurable duration.
• deathing — Changes a survivor's revive count to trigger the black-and-white critical state.
• glowing --- Let entity glow.

Examples:

/effect give @s adrenaline 30 /effect give @a deathing /effect clear @s adrenaline /effect clear @a

Unlike ordinary Minecraft effects, deathing does not have a duration. It modifies the survivor's revive state.

6. Custom Gamemodes

The /gamemode command uses a custom system rather than Minecraft's Survival, Creative, Adventure, and Spectator modes.

• 0 — Normal mode.
• 1 — Semi-God mode (low-health protection).
• 2 — God mode (damage immunity).

God mode also protects players from this addon's /kill command.

Semi-God mode does not guarantee protection against every instant-kill mechanic.

7. Attribute System

The /attribute command has been significantly extended to support L4D2's scripting and engine properties.

Three attribute namespaces are available:

• convar: — Access and modify Source engine console variables.
• netprop: — Access and modify entity network properties.
• scope: — Create, read, modify, or remove entity ScriptScope properties.

Examples: