I believe in one of the books an elf makes his way through a maze to find a black crystal of some sort. When he leaves the maze there is an army outside waiting for him and he uses it to kill the army.
Also I believe in another book of same series, they are trying to make a sword. They find a blacksmith with an amazing sword already made. He won't sell it, but he says if they get the material he'll make them a new one.
Edit:(All credits to CBredlow for the answer.For a more detailed answer look below.)
Then name of the first book in the series that contains both of my above scenarios in the books is "The First King Of Shannara."