It's been over two years since the last Suikoden game (Suikoden V) came out, so it was about time a new Suikoden game to arrive. No word yet on when Suikoden Tierkreis will be coming out.The Nintendo DS-based title's development is currently 50% complete. Its world will feature various races and cultures and promises to be full of change. The world can be navigated on a worldmap. The game's protagonist is a young man named Jail, the heroine's name is Marika. A new race named Popas is also set to debut in Tierkreis. Battles will feature a "four active party member system plus alpha." Critical hits, character-specific special techniques and (if a particular character is a party member) cooperation attacks have been confirmed to be part of the player's offensive arsenal.
Source: http://www.rpgfan.com/news/2008/1360.html
EDIT: The official website for Tierkries is now up (in Japanese), but there's not much content on the website yet. You can check it out here: http://www.konami.jp/gs/game/genso/tierkreis/
