The Heroes by Joe Abercrombie

The Heroes is another excellent addition to Abercrombie's First Law books.  It's a standalone novel, but I recommend you read his previous four firstly because some character background is assumed.  It is just as gritty as the previous books, but the geographical focus is a bit tighter and there are plenty of maps to let you know how the battle is progressing.

I like Abercrombie's writing style which is violent, but with intrigue to balance it out.  Like Martin, he's not afraid to kill off major characters so don't get too attached.

I highly recommend this book.