quake ?

All of the Quake data files remain copyrighted and licensed under the
original terms, so you cannot redistribute data from the original game, but if
you do a true total conversion, you can create a standalone game based on
this code.

I will see about having the license changed on the shareware episode of
quake to allow it to be duplicated more freely (for linux distributions, for
example), but I can't give a timeframe for it. You can still download one of
the original quake demos and use that data with the code, but there are
restrictions on the redistribution of the demo data.

If you never actually bought a complete version of Quake, you might want
to rummage around in a local software bargain bin for one of the originals,
or perhaps find a copy of the "Quake: the offering" boxed set with both
mission packs.