but as RPA said, if you don't do a good job you're certainly going to be called a copycat. So you can't really be sued, but you won't have much literary respect either. Again, unless you do it well. For example, no one's sued Paolini for his Eragon books, but the first book (at least) is essentially fan fiction borrowing from many different authors smashed into one book and it's not pulled off well. Thus, despite his popularity, you don't exactly hear people lauding his writing skills