Perhaps I abbreviated it too much. The full translated name is 'Pocket Monsters Black/White Official Guide: Wireless Play: Special Secrets Book', Serebii likely translated its function and not its name.
It has 'special secrets' not covered in other guides such as Unity Tower, the 50-trade Master Ball, full Hi Link and Black City/White Forest mechanics and about 80 pages of DW info. Nothing really about the characters.
It has 'special secrets' not covered in other guides such as Unity Tower, the 50-trade Master Ball, full Hi Link and Black City/White Forest mechanics and about 80 pages of DW info. Nothing really about the characters.