This game follows the plot of “Harry Potter and the Half-Blood Prince,” as Harry and his pals prepare for dark sorcery from without (the rise of Voldemort) and from within (just who is “the Half-Blood Prince?”) Players duel with wizards, mix potions, fly on a broom in a Quidditch match, and even take a detour into romantic subplots. It is available on Wii, PlayStation 3, Xbox 360, PC and Macintosh. Launch date: Sept. 30, 2009.