Marathon Infinity takes the closed universe of the Marathon
series and blows it wide open. The solo/co-op campaign,
"Blood Tides of Lh'owon," is a 20-level scenario sporting new
textures, weapons, and aliens. More than that, the scenario sheds
a surprising new light on the story's characters and the
meaning of events. Having defeated the Pfhor and reawakening
the ancient remnants of the S'pht, the player now faces a
world where friends become enemies and all is not what it seems...
Marathon Infinity is the most popular Marathon game in online play,
and is compatible with hundreds of community-made maps.
This release includes the classic graphics, and revamped high-definition
textures and weapons.
source: ubuntu package description