House Atreides was the main house in the Dune books. These were the "good guys" and this fact remains in the game. House Atreides is from the planet Caladan, which contrasts the desert planet Arrakis (known as Dune). Caladan has a lush, tropical climate. In the book, the Harkonnens were the Atreides major enemy while on Dune. Of course, Paul Atreides, with the help of the Fremen, took over Dune, and thus, took over the Empire. And then Paul's kid goes out into the desert and turns into this half-human, half-sandworm creature, but that's not until the fourth book, so I won't get into it.