A serious bug has been uncovered in Oblivion expansion Shivering Isles, which renders the game unplayable after as little as 50 hours.
The problem is being caused by scripts for a handful of new NPC characters, which are using up several ID numbers (allocated to new objects) every frame. This means that internal space for these numbers will be exhausted much sooner than intended, making freshly created objects eventually disappear from the game world.
So, depending on your frame per second count, you will have a drastically reduced possible play time before everything goes awry. The Xbox 360 version of the game runs at around 30 FPS, giving you 80-150 hours before things to awry, but PC users running at a faster rate will encounter problems sooner. Apparently the original game would run out of ID space after 1000 hours of play time. But strangely no one could confirm this.
The bug becomes effective as soon as Shivering Isles is installed, regardless of whether you're exploring the new content or not. Developer Bethesda says it is aware of these problems and is working around the clock to fix them.
"Regarding the issue in which Form IDs are being used at a high rate in the Shivering Isles content; we are aware of the issue and we are currently looking into a solution," a developer contributed on the official forum."We appreciate your patience, especially from those of you affected by this issue, as we carefully work out a fix that will correct this problem without adding any new issues."
So, until then, Bethesda suggests you do one of a few things. X360 gamers will want to make a copy of your saved game for safe keeping, and either lay off playing Shivering Isles for a few days until the problems are confirmed and addressed, or start a new character to explore the content, as others won't be affected by this.
PC users should head over to the game's wiki and select one of a selection of places to download the patch from - immediately! There is also a repair tool that will attempt to alter your saved game using some sort of techno-wizardry, but it's currently unsupported and could lead to broken characters and a few fantasy tears.
Shivering Isles is the first proper expansion pack for Oblivion, which introduces the wacky realm of Deadra Prince Sheogorath. This crazy fellow will soon be asking for you help to repel invaders to his plane of Oblivion, which sees you undertake progressively more bizarre tasks.
We recently got our hands on it and were somewhat underwhelmed. It was great to be back in the lands of Oblivion, but the addition seemed to lack the spark of the original. You can read our Shivering Isles review elsewhere on Eurogamer.