BBM did a whopping 50 sets in 2013, although in some ways what stands out this past year is what they didn't do for the first time ever. I believe that this is the most sets BBM has done in one year, but I could be wrong. The 2013 sets were released over a 14 month period starting in November of 2012 and finishing up early in December of 2013.
22 of the sets BBM released this past year were the 2013 edition of sets that BBM produces each year - the "flagship" sets of 1st and 2nd Version as well as the Genesis high end set, the individual pack based sets for each of the 12 NPB teams, the "Farewell" box set commemorating players who retired at the end of the previous season, the "Rookie Edition" set featuring the players taken in the previous fall's draft, the box set for the Tokyo Big Six collegiate league, the "Rookie Edition Premium" box set featuring high end cards for the year's top rookies, the "Historic Collection" set (this year's theme was "Great Uniform Numbers") and the two pack based sets for the cheer/dance squads for teams - Hana and Mai. Missing from this year's releases, however, were the annual All Star and Nippon Series box sets that BBM had done each year since 1991, their first year producing cards. In addition, BBM did not do a box set for the Premium Malts old timer game held in July - they had done so for the three previous games.
BBM issued five box sets that were team-specific. The Young Fighters, Young Lions and Young Tigers sets all (obviously) highlighted the young players from each of those teams. The "Yui Carp" set was a simple but small (only 18 base cards) team set. The Eagles First Crown set was purportedly to celebrate the Eagles winning the Pacific League pennant for the first time but it's really just a straight team set - there are no "highlight" cards or anything that actually show the team clinching.
BBM also issued five "single player" box sets. Four of these were to celebrate players who retired in 2013 (or in one case, late in 2012) - Hideki Matsui, Shinya Miyamoto, Shinjiro Hiyama and Tomonori Maeda. (The Miyamoto set is also kinda-sorta a Swallows team box set.) The other "single player" box set was called "Legend Of Invincibility" and celebrated Masahiro Tanaka's 24-0 season - the set features a card for each of his wins during the season.
Where BBM really took off this past year was in historic (OB) sets. After only doing three in 2012, BBM did a total of 14 this year (including the aforementioned "Great Numbers" "Historic Collection" set). They did team based anniversary sets for the Hawks (75th), Baystars (20th as "Baystars") and Fighters (10th year in Hokkaido) as well as a box set for the Hawks celebrating their three Nippon Series championships in the 25 years they have been in Fukuoka. They also started a new series of team based OB sets called "Legend" - they issued a set for the Giants celebrating the players who had played in Shigeo Nagashima's two terms as manager and a set celebrating the players who played for the Tigers in the 1980's. They issued two sets featuring only "gaijin" players - "Legendary Foreigners" and "Deep Impact". They used Yoshio Itoi's abrupt trade to Orix last spring as an excuse to produce a set featuring great trades in history (The Trade Stories) and did a set featuring great moments in All Star games in the 1980's (All Star Memories '80's). BBM also issued three more box sets in the "Greatest Games" series that they started in 2012 - the games featured the Giants/Tigers game on 10/22/73, the Buffaloes/Blue Wave game from 9/26/2001, and the Tigers/Swallows game from 10/16/1985.
The remaining five sets BBM did are a group of odds and ends. They did a box set for rookies and young players called "Icons - Hope" that may be the replacement for the "Diamond Age" box set BBM did in 2011 and 2012. They also did a set called "Our Friends" which features all the mascots for all 12 teams. Both of these sets may become annual issues. One set that I'm hoping becomes an annual issue was the Classic set which featured current players on cards using the 1991 BBM design, kind of BBM's version of Topps' Heritage sets. The final two sets BBM issued this past year were sets that celebrated players from Kyushu and the Osaka area.