The Next Tetris: Online Edition contains two separate versions of Tetris. One is classic Tetris, with no frills, power-ups or special blocks that do anything other than take up your space in the well until you either get rid of them or they spill over the top, ending your game.The other version is The Next Tetris, which takes the game and soups it up, presumably for today's "faster-paced generation." At the heart of the The Next Tetris are Multiminos. These are Tetris pieces made up of multiple colors. When they land, they bind with other pieces of their color, and if the colors don't match, the remaining blocks "cascade" down into spaces below, provided there are any. This sets up for combo opportunities beyond the simple four-lined Tetrises of the older version.
There are also additions to the two-player mode. Your ability to quickly clear lines will now cause your opponent's well to spin in different directions, become dim and hard to see, or change colors to screw up his cascading schemes. You can also play both versions against another player online, thanks to the Dreamcast's built-in modem. ~ Jon Thompson, All Game Guide