Second **** contains four remakes of Battlefield 3 maps, including Gulf of Oman, Operation Metro, Caspian Border, and Operation Firestorm. China Rising will be Battlefield 4's first DLC pack, and is free to anyone who pre-orders the game. A membership to Battlefield Premium unlocks all add-ons two weeks early.
Battlefield 4 launches later this month. Look for IGN's review closer to its release.