Sega put that Valkyria Duel trademark to use and just announced a card game with characters from the entire Valkyria Chronicles series. Valkyria Duel has over 200 characters and 3D battle scenes.
NHN Hangame will release Valkyria Duel for PC browsers. A smartphone version is slated for release later on. Valkyria Duel is free to play and is supported by virtual item sales. Hangame is running a user test for Valkyria Duel later today.