Opening 1.e4 c5 2.c3 d5 3.exd5 Nf6 for Black repertoire. This book, the first work devoted to this opening, contains analyses and 34 in detail annotated games. This is not a shady gambit but it is a weapon that has been used by several grandmasters, including World champion Magnus Carlsen. The gambit has the advantage of being unexplored and is still quite unknown. Series Opening Hacker Files 7.