The Solus Greatsword is a legendary weapon found in both "Fable" and the special edition "Fable: The Lost Chapters." The Solus Greatsword is located in North Bowerstone, which you cannot visit until you have completed the story missions in the arena. Depending on your version of the game, there are up to two ways of obtaining a Solus Greatsword in North Bowerstone. In both games the sword can be purchased for an expensive price, or you can also receive a Solus Greatsword as a gift from Lady Grey after successfully wooing and marrying her.
Purchasing the Solus Greatsword
Raise the money required to purchase the Solus Greatsword. The Solus Greatsword has a base value price of $69,825 although the nature of your character's alignment may cause the sword to be slightly more or less expensive. Earn money by completing side missions and jobs and by winning wages in mini games and gambling.
Travel to the weapon shop located in North Bowerstone. Use your map to find the easiest path to the shop.
Talk to the shopkeeper to purchase the Solus Greatsword.
Lady Grey and the Solus Greatsword
Talk to Lady Grey in Bowerstone North. She will ask you for several gifts and favors in order to win her affection.
Purchase a Black Rose from the shop in Bowerstone North and bring it to Lady Grey. Next she will ask you for a house.
Purchase a house for Lady Grey. There are several affordable options in Bowerstone South. After completing this task, you can sell the house to regain some of the money you lost.
Talk to Lady Grey again and she will ask you to find her necklace. Gather information by talking to all the people that show up as green dots on your map. Then travel to the Memorial Garden in Oakvale. Sneak up on the men talking in the garden and you will hear the location of the necklace. Find the necklace on the western beach of Oakvale, between two upturned boats.
Return the necklace to Lady Grey and she will ask you to defeat a warrior named Thunder. Travel to the Bowerstone Jail and challenge Thunder at Headman's Hill. Use a combination of your strongest attacks to quickly take him down. Avoid Thunder when he uses his lightning attack as he will be temporarily invincible. As you wear him down the fight will take you down to the lower part of the hill, then a nearby cave.
Talk to the Demon Door in the cave after defeating Thunder to exit. Return to Lady Grey and she will agree to marry you. Once married, keep giving her gifts and using romantic social actions to keep her happy. When you leave the town and come back, there is a chance she will give you a gift. The gift is always a randomly selected item from the North Bowerstone shop --- including the Solus Greatsword.