CDKeys offers Steam download preorders of Batman: Arkham Knight for Windows, Mac, SteamOS and Linux bundled with the Harley Quinn Story Pack DLC for $29.99. "Like" the CDKeys Facebook page to receive a unique coupon code to drop it to $28.49. (There's a Facebook link on the top of the page.) That's $17 below our mention from three days ago and the lowest price we've seen. (It's a current low by $17, although most sellers charge $60.)

Note: It's is scheduled for release on PC on June 23 and will be available for SteamOS, Linux and Mac in Fall 2015.