|DDR 2nd Mix with beatmaniaIIDX CLUB VERSiON has a completely different song list from 2nd Mix, instead featuring all 13 songs from beatmania IIDX CLUB VERSiON. The two arcade machines are designed to be linked to each other, allowing simultaneous play by two to four players (up to two on each machine). One song is selected by the IIDX player(s), and is then played on both machines. For the DDR player(s), only one difficulty is available for each song, although there is a different step set for Doubles mode. If a player on either machine fails the song, play continues as long as at least one player is passing.|
CLUB VERSiON also introduced Vivid mode, which changes the color-cycling for arrows based on their placement within each bar of music. This allows players to better time their steps based on visual information, and has been enabled by default in most subsequent DDR games.
Game description from www.arcade-history.com