Since the announcement of their newest fighting game project, NetherRealm Studios have been consistent with two promises: this isn't Mortal Kombat with DC characters, and there's going to be a whole lot of content!

Injustice: Gods Among Us is taking full advantage of the wealth of material DC Entertainment have to offer, tapping in to everything from the comics themselves, to other video games!

Walmart have joined the bonus content arms race, offering exclusive DLC costume packs inspired by the 2011 video game - Batman: Arkham City!

Batman, Joker and Catwoman [pictured right] get the Arkham City treatment [no pictures available]. The pre-order purchase bonus is seemingly only available for PlayStation 3 and Xbox 360. Update: An image of the Arkham City DLC designs has emerged [via Giantbomb]. Thanks to C-Sword for the tip.

Pre-orders from Gamestop will receive exclusive Red Son game content, featuring alternate costumes for Superman, Wonder Woman and Solomon Grundy [below]. The pack also includes twenty challenge missions set within the Red Son universe.

Superman: Red Son is the Eisner Award winning 2004 mini-series by Mark Millar and Dave Johnson. The popular DC Comics Elseworlds series tells the tale of a world where Superman landed in 1950s Soviet Russia, raised to be a communist hero.

The Gamestop offer is only available with orders for PlayStation 3 and Xbox 360. Australians can find the same deal at EB Games [PS3, 360; via Gamespot]. Update: Fans in the United Kingdom can pre-order the Red Son DLC edition via GAME [PS3, 360; via MKRAYDEN]

Injustice: Gods Among Us arrives on US home consoles April 16, with a simultaneous Australian release (April 17). Additional bonuses are available in special editions. Discuss all the versions and more on the DC Universe Injustice forum. Thanks to blackcyborg for the tip. Found something cool? Let us know about it.