US PC game charts: May 28-June 3

On June 1, Valve Software's budget-priced stand-alone adventure Half-Life 2: Episode One was released in boxed, retail form as well as through the developer's own digital distribution service, Steam. While the game's online sales figures weren't taken into account, the industry-tracking NPD Group's latest US PC sales chart indicates that the boxed, retail version of the game was the second-best-selling title at retail for the week ending June 3.

Blizzard Entertainment's massively multiplayer PC retail champ World of Warcraft reclaimed the top spot on the charts after spending the previous week playing second fiddle to 2K Games' The Elder Scrolls IV: Oblivion, which dropped to fifth place. Electronic Arts' The Sims 2 continues to show its longevity, taking the third spot in the charts, with its Open for Business and Family Fun Stuff expansions trailing in sixth and seventh place, respectively.

While the previous week's chart featured a pair of Microsoft-published real-time strategy games in Age of Empires III and Rise of Nations: Rise of Legends, both the genre and the publisher were wiped off the charts this week. That was partly attributable to Ubisoft's turn-based strategy game Heroes of Might & Magic V landing the fourth position on the charts, with its more expensive limited-edition package sliding in under the wire in the 10 spot. Sealing the deal and shutting out Microsoft and its real-time strategy games were NCsoft's massively multiplayer Guild Wars Factions in eighth place and EA's first-person shooter Battlefield 2, securely entrenched in the same ninth place it occupied last week.

NPD's US PC sales charts are based on the number of units sold at 23 of the tracking firm's retail partners.