At the end of Overlord you killed the original Overlord and took complete control over the land - but someone wasn't happy with that. Your jester decided to take things in his own hands and executed a powerful ritual to summon the forces of hell themselves. He succeeded. Everywhere in the world strange portals opened up, leading down into the Abyss. As this is your empire, you are going to investigate and add hell to your land.
The gameplay of Overlord: Raising Hell remains the same as in the original game, but besides the new levels, there is also a new difficulty level called "Legendary" and recipes for unique weapons and armor can now be found down in the Abyss. There are always new challenges awaiting the Overlord down in the tower pit.
There are eight new multiplayer maps waiting and it is now possible to play in front of the same computer using a split-screen mode.
The retail version of Overlord: Raising Hell includes the original game and was only released in Germany (Windows). The PlayStation 3 version includes the original game and the expansion, as the base game was not released for the platform. For Xbox 360 owners the new content is available as a free download.