Home

Welcome to the blizzget wiki!

Here you can find a documentation for CASC format and Blizzard CDN storage.

The documentation is based on (slightly outdated) information found on wowdev Wiki and CascLib source code.

Download workflow

Here are the steps required to download a whole game from Blizzard CDN storage.

Obtain list of CDNs and versions

These two files can be downloaded using the global configuration URLs. The /cdns file is used to build URLs for all the other files, and the /versions file is used to locate the cdn-config file.

Get cdn-config and build-config

CDN config contains the list of data archives, and the list of game builds. Select one of the builds and download the corresponding Build config file, which contains the hashes for the key files in the archive.

Download and unpack the encoding file

Using the second encoding hash in the build-config, get the [encoding file](Encoding file) from the CDN data URL, and extract it from the [BLTE container](BLTE Containers). This file will be used to locate the download and install files later on. It is also one of the files that has to be stored in the CASC data folder.

Get the download and install files

Using the encoding file, translate the download and install content hashes to their CDN keys, download them from the data URLs, and extract them from BLTE containers. These two files also need to be stored in the CASC data.

Get the data indices

Using the list of archives in cdn-config, get all the .index files. They will be used to download the majority of the actual game files. The files that cannot be found in the archive indices need to be downloaded individually.

Download all required files

From the [download file](Download file), build the mask of required files, and download them from the CDN data archives or individual URLs. It is recommended to use the partial download headers to avoid having to download the entire archives, as it will save a lot of time.

Install files

If you want to try running the game (which is mostly pointless as you will probably be unable to log in), follow the instructions in the [install file](Install file).

Create the .build.info file

Construct a .build.info file similar to the one found in other games.

Done!

You can now try running the game. Make sure to supply a --launch command line argument, as it will otherwise simply open the Battle.net launcher and inform you that you are using the wrong version of the game.

Alternatively, you should be able to extract the game files using CascLib or CascView (the latter will probably fail for some reason).