Dungeon Siege IV needs to stay true in story and visuals to the first Dungeon Siege game (improved graphics of course), with the customization options of Dungeon Siege 2 (class system, race, appearance, leveling etc). Functionally the game should build upon the mechanics of the first two. Keep the RTS/Diablo like controlling (left click for move and right click for attack) and improve on the power function you could use in Dungeon Siege 2. More enemies and of course they should respawn after a while. The most important bits: Dont make it MMO. Dont just make it for the PC. And keep adding content until people start screaming for a NEW DUNGEON SIEGE GAME!