Knights of the Nine is an upcoming add-on pack for Bethesda's smash-hit The Elder Scrolls IV: Oblivion. To date, it is the largest add-on content Bethesda has created for Oblivion and it'll easily rival the size of a standard expansion pack. After getting my feet wet with a preview of the expansion, it's pretty clear that this will provide more content for fans of not only the game but for gamers everywhere.
Knights starts out with an attack on Anvil's Chapel of Dibella. When you venture there, you'll meet a prophet who foretells a prophecy of an ancient evil (named Umaril) arising from the past to lay waste to all who oppose him. But in order to combat him, you'll need to acquire the equipment from the legendary warrior who laid the smack down on him back in the past. Note this quest-line is only for good folks, but that doesn't mean you evil folks are immediately ruled out.
It'll set you back 800 Microsoft Points on Xbox 360, $9.99 on the PC or $19.99 for the retail version.