1up is reporting that after yesterday, fans alerted Bethesda Softworks to a game-breaking bug discovered in The Elder Scrolls IV: Oblivion: Shivering Isles, which started to appear after gamers had cleared 50 hours of gameplay within the expansion. Bethesda has already issued a beta patch to start solving the issue. Because it's a beta, however, the studio warns of casual users hopping straight in, as there could be unforeseen issues that occur upon installation.