ES4: Oblivion - The Vile Lair Cometh @ Official Site

This Thursday, evil characters will rejoice when a new downloadable dungeon, The Vile Lair, makes its debut. For both PC and XB360, the download will cost $1.89/US.

This underwater hideout provides your infamous character with safe haven. Those willingly inflicted (or shall we say graced?) with vampirism will find a means to feed, and if necessary, a means to cure their infliction. Hire evil minions, pray to the dark god Sithis, and a host of other functions await.

You can read more about it here.
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