The previously announced ‘singleplayer’ downloadable content (DLC) pack for Bioshock 2, the Protector Trials, is now available to purchase and download for the Xbox 360 via Xbox LIVE Marketplace, for the measly sum of 400 MS Points.

This DLC will soon become available for the PS3 via the PlayStation Network (for $4.99) when the US PlayStation Store receives its weekly content update later today. European PS3 gamers will have to wait until tomorrow to get the pack.

Protector Trials for Bioshock 2 places you back in the boots of the Big Daddy and tasks you with protecting Little Sisters from “swarms of corrupt Splicers who are hell-bent on stealing the precious ADAM that she gathers from corpses.”

The content was created by 2K Marin, the same team that brought you the singleplayer portion of Bioshock 2, contains six new maps, new Achievements and Trophies, as well as new unlockables. Here’s what you can expect from the pack:

• Six new maps: three unique difficulty levels, each based on favorite locales from BioShock 2;
• New unlockables, including never-before-seen concept art and videos;
• Seven new Achievements/Trophies

You can see a keen trailer for Protector Trials through the link above, or you can browse through El33tonline’s previous coverage of Bioshock 2 (including our review of the game) for more information.