The bundle is available for PC, Mac and Linux, and includes Marathon, Marathon 2, Marathon Infinity and an open source version of the Marathon engine, Aleph One. A high-resolution graphics overhaul has been given to all three games in the pack and can be downloaded here.
EGM’s TAKE: Classic shooters for free? Can’t really grumble at a chance to enjoy a bit of nostalgia based killing.
Source: Marathon SourceForge