Release is upon us!
http://alienisolation.com/news/2015/01/13/a-third-add-on-pack-a-new-challenge-modehttps://www.youtube.com/watch?v=ZT0ok2pLbFQ&oref=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DZT0ok2pLbFQ&has_verified=1"'Safe Haven' will allow you to play as new character Hughes, Sevastopol's Station's Communications Manager.
Trapped in a safe room and desperate to escape, Hughes' only chance is to take on ten tasks given at the communications terminal in the lower decks of the station.
Every task is one step closer to escape but will require the utmost stealth and skill as Hughes confronts the station's life-threatening challenges – a crumbling environment and the toughest foes - as he works to restore communications and get away.
In 'Safe Haven', be ready to experience a different side to Survivor Mode. With a far larger challenge map and only one life to survive with, each level will test your skills with new objectives, a different enemy type and the risk that one wrong move will be your last.
Completing each challenge will unlock rewards and points, with new items to collect and craft. Gather enough points and you'll be able to trade them in for a chance to save and bank your progress.
Should you fail at any point, you'll be taken back to your last saved challenge but it comes at the cost of your final score and the place on our leader boards.
Will you favour safety over the highest score? How will you survive? Get a taster of what's waiting for you in our trailer:"
The official page doesn't reference the Marathon mode GameSpot mentions.
They've confirmed on Facebook that Marathon mode is also included.