You know one of the top maps ATCS? It contains media that is non-free culture.
So, in your maps folder that came with your game: (if you installed it through synaptic or apt-get , then it can be found at
You can open it with for example "Archive Manager" and inside you find the file There under [ other notices ] you find
Also textures from shaderlab:
textures by yves allaire fall under this license:
which is the only mention of commercial rights, meaning that it probably falls under a similar license to cc-by-nc-sa , so you are not allowed to use it for commercial purposes.
Other non-commercial applications are considered on a case-by-case basis via e-mail.
So the stated media being under CC-BY-SA 2.5 is false. I guess they didn't think it priority one to make it clear WHAT is licensed under WHICH license.
A quick look. The popular map Niveus also has textures from yves allair: Quick link if you've installed Tremulous from Synaptic or apt-get or any other package manager:
(open map-niveus-1.1.0.pk3) and inside you find the file This can help also as a reference on why Tremulous is in Multiverse