Right now, developer Relic is the veritable schoolyard bully of strategy gaming - stealing lunch money and handing out wedgies to all challengers to its towering Dawn of War franchise and its recent strategy triumph, Company of Heroes.
A bully perhaps, but an incredibly generous one - Dark Crusade is standalone, and doesn't require the original Dawn of War to play. You may lead any one of the seven races in the thrilling single player campaign, and add the Tau and Necron to your lineup for multiplayer beat downs. Dark Crusade is an enormous amount of top-drawer content for $29.99, and newcomers may rightly mistake it for a full blown sequel. Highly recommended.