Once you discover the glowing door, you are informed that several adventurers have entered and either disappeared or returned insane. Unlike previous expansion content, where the new quests just show up in your journal, it takes about a day or two of in-game time before you begin to hear rumors of a strange portal that has appeared somewhere near Bravil.
And no, even though he sounds like a certain Spongebob character, they aren't done by the same voice actor. Some of the best acted lines come from Sheogorath himself, who perfectly reflects the madness of his realm. Every NPC is voiced well, though some lines do come off as still – an unfortunate byproduct of the stiff character animations during conversations. While exploring, soft flute-filled music plays only to give way to deep, brassy tones during action and battle scenes. Much of the same music from Oblivion is reused in Shivering Isles. The towns on the Mania side are well-kept, while Dementia's are filthy cesspools. This districting even carries over into the cities that populate each section. Dementia, on the other hand, is fog-filled and comprised predominantly of dead forests, ruins and swamp land that is reminiscent of the lands seen in Morrowind. Mania is a bright, deliriously happy place dotted with lush forests, giant multi-colored mushrooms and clear lakes. The Isles are split into two sections, Mania and Dementia, with the look of each reflecting its name. After agreeing to step into the Isles, the black walls explode in a flourish of dark purple and blue butterflies revealing a bright, sunlit forest. Rather than seeing the vast new world ready for exploration, you are dumped in a black-walled room where the only thing you hear is the clicking of a metronome on a nearby desk. Nowhere is this best illustrated than when you first enter the Isles. Artistically, however, it pushes the game’s visuals in a completely new direction. The Isle's residents are just as unattractive as Cyrodil's and there are still times where grass looks like it is growing beneath your feet.
The expansion doesn't do much to improve Oblivion's technical visual shortcomings. Instead, the game offers up a new area to explore that is about a third of the size of the Cyrodil, a sizeable quest involving a Daedric Prince, a new major city, several small towns, new craftable armor and weapons and 500 new Achievement Points. The Elder Scrolls IV: Shivering Isles is the game's first major expansion, adding more than just a new dungeon or quest. The Elder Scrolls IV: Oblivion was one of the Xbox 360's first "Must Play" titles and, thanks to downloadable content, the game has proven to be an enduring favorite.