Pokémon Conquest — aka Pokémon + Nobunaga's Ambition in Japan — was the best-selling Nintendo title in the Land of the Rising Sun last month.
The strategy crossover was released on 17th March, meaning it shifted 242,192 units in two weeks. In third place was Kid Icarus: Uprising, with 144,468 sales in the ten days following its 22nd March release.
Top dog was PS3's One Piece and Dynasty Warriors mash-up One Piece Pirate Musou, which racked up an impressive 770,873 sales after its release on 1st March.
Here's Japan's top ten best-selling games for March 2012:
[PS3] 01. One Piece Pirate Musou (Namco Bandai, 03.01.2012): 770,873
[NDS] 02. Pokémon Conquest (Pokémon, 03.17.2012): 242,912
[3DS] 03. Kid Icarus: Uprising (Nintendo, 03.22.2012): 144,468
[PSP] 04. Shining Blade (Sega, 03.15.2012): 138,959
[3DS] 05. Hatsune Miku And Future Stars Project Mirai (Sega, 03.08.2012): 111,465
[3DS] 06. Mario & Sonic at London Olympics (Sega, 03.01.2012): 105,454
[PSP] 07. Yakuza Black Panther 2 (Sega, 03.22.2012): 94,833
[PSP] 08. Mahou Shojo Madoka Magica Portable (Namco Bandai, 03.15.2012): 78,575
[3DS] 09. Monster Hunter 3 G (Capcom, 12.10.2011): 76,850 (total 1,289,794)
[PS3] 10. Street Fighter X Tekken (Capcom, 03.08.2012): 72,079