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Lambda - Half-Life 2 Co-Op

Have you ever wanted to play the Half-Life 2 series with your friends online? Then Lambda is exactly what you are looking for. Lambda aims to provide seamless multiplayer support for the Half-Life 2 campaign maps, as well as user-created campaigns.

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀[discord.gg][github.com]


- Level scenes reworked with checkpoints to be multiplayer friendly, players won't be forcibly teleported
- Full player and object transitioning between levels
- Enemy scaling based on skill level and player count
- Visual improvements
- Legacy Half-Life 2 aspects such as view bob, view lag, sprinting, AUX power counter, and more
- Survivor mode with respawn checkpoints
- Ability to command friendly NPCs via the context menu
- Medkits for players to heal eachother
- Dynamic crosshair
- Underwater bullets
- Custom Gravity Gun including the mega version with glow color customization
- Passenger seats
- Voting system
- Mapscripts for each campaign map for modifying logic and extra gameplay enhancements
- Ability to create your own story
- A menu (F1) where you can change various gamemode settings, player settings and cast votes
- Merged episodic animations in the base NPC model
- Easter eggs




The best way to report bugs is via GitHub, use following link[github.com] to submit a new issue or by posting the issue in our Discord in the #bug-reports channel. We do not recommend posting bugs in the comment section below.


- How to start the campaigns?
- Select the gamemode and start a new multiplayer game with the map "d1_trainstation_01" if you want Half-Life 2, otherwise for Episode 1 select map "ep1_citadel_00" and for Episode 2 "ep2_outland_01".

- How to change playermodel and settings?
- To access the menu press F1. Here you can change your playermodel and client settings. If you are an administrator you can also change server settings.

- What about Episodes or Half Life 1?
- Episode 2 is currently under development, as for Half Life 1 check this gamemode out made by TheMostUpset

- Using custom weapons or spawning props?
- There is no custom weapons support at the moment. You can give yourself weapons either through Lua or the "give *weaponname*" command. The spawnmenu does not exist.

For a more in depth FAQ click here


Half-Life 2: Cosmonaut
Half-Life 2: Calamity


This is currently a work-in-progress, but will be documented soon. Here are the current specifications:
1. Whatever Half-Life 2 uses already works
2. For transition support, your map must have an info_landmark, trigger_transition, and trigger_changelevel. Check out the Valve Developer Wiki for more information
3. Information about round setup and other basic rules