Custom Campaigns

Custom Campaigns, also known as Community Campaigns, are community-created campaigns that can range in size from a full campaign, to a single chapter. Some custom maps are specifically designed for game modes like Scavenge and Survival. Custom content can only be created and used by PC users. Xbox 360 players are unable to use custom content due to technical and financial difficulties regarding porting community-based content over.

Valve is supportive of custom content. They have a SDK for each of their games including Left 4 Dead and Left 4 Dead 2, which allows for easy creating and installing of custom campaigns. They have also released audio recordings by the voice actors of the Survivors for use in specific custom campaigns and feature some custom campaigns on their online blog, as well as uploading specific custom campaigns onto the official servers for more accessibility. With the exception of these featured campaigns, most custom campaigns can only be played on Third-Party Servers or Local Servers (including Single Player mode).

After the February 7, 2013 update, Steam introduced the Steam Workshop where users can upload their custom created maps or content. This system allows custom campaigns and other add-ons to be browsed, interacted with and downloaded directly through the Steam client, even while in-game. Manually downloading and installing content from other sources is still supported however.

How To Install
Once a custom campaign is downloaded from a site, the VPK file is simply placed into the addons folder found in either Left 4 Dead or Left 4 Dead 2 folders. Campaigns are generally created for a certain game; a campaign created for Left 4 Dead may not always work for Left 4 Dead 2, and vice versa, so be aware which game the custom campaign is for before installing.

Some custom campaigns may not be encased in a single VPK (that could be opened with GCFScape;) the file may be a zip or rar file containing a number of .bsp (that could be decompiled to a .vmf file using BSPSource) and .nav files as well. In this case, the file will generally have instructions on where to place them, but usually, the .bsp and .nav files, along with related .txt files, will be placed in the maps folder.

Alternatively, using Steam Workshop, any campaigns that are available on the Workshop can be downloaded by clicking the "subscribe" button. Some campaigns are either packaged in one content, or split in parts (due to workshop maximum file size limits) where all parts must be subscribed to in order to play. After subscribing, the workshop content will download and be ready to play simply by launching the game.

The above instructions will apply to most community content, but occasionally, some more complex content may require additional steps to install correctly, so be sure to check for extra instructions given out by the developer of the content you wish to install.

List of Full-Length Custom Campaigns
Here is a list of custom campaigns which have been noted by their creators to be 'complete', or at least in the final build, with no major updates planned unless concerning bug fixes. These are based around Campaign mode, with the length and number of maps being roughly comparable to standard canon Campaigns. There may be optional modes within the maps catering to Versus, Scavenge and Survival. Descriptions are taken from where the map is found, unless no description was given.