The second Kate Walker adventure game, Siberia 2, is the latest ‘On the House’ freebie from EA through Origin. As per usual with the On the House system, it’ll stick around for an undesignated amount of time. If you grab it at any point, it’ll remain in your account, so if you have any interest you may as well do that now.
An Origin account is required, of course. That’s free, aside from giving EA a few of your details.
After a few delays, the third game seems to have a more concrete release date of 20 April (Europe). Making Siberia 2 free is presumably an effort to get a few more people interested in the series ahead of the next sequel. Not a bad plan, really.