Bandai Namco and Tariser Studios’ atmospheric horror adventure game Little Nightmares, released in April 2017, is free on Steam.
You can get the game for free until 20:00 on 30 May. When you add it to your account before that date, you keep the game.
Company of Heroes 2 and its standalone single player expansion Ardennes Assault were also free on Steam yesterday, and you can add them to your account by 8pm on May 30.