SH Monsterarts Mecha King Ghidorah will be a limited web shop item. The mechanized version of Monster Zero looks pretty fantastic and comes with a load of features and accessories, which work well with their previously released Godzilla SH Monsterarts figure. The 250mm tall (almost 10″) figure will sell for 19,440 Yen (about $187 USD). It also includes three Dorats, from the 1991 movie Godzilla vs. King Ghidorah. The Dorats were mutated by a nuclear blast that caused them to fuse together and become King Ghidorah.
Update: Bandai has put up an official page for the next massive MonsterArts release. Also they updated the price being $199 US (about $10 higher than previously posted) and the release is set for March 2015.