Both, it’s part of Digital Eclipse’s Gold Master Series, like Llamasoft: The Jeff Minter Story and The Making of Karateka.

From their website:

More than 15 playable classic games from the series’ history are featured, including many being released for the first time outside Japan. Battle your friends in the multiplayer cult favorite Tetris Battle Gaiden, create massive explosions to clear lines in Super Bombliss, and see where it all began in 1984 with an accurate recreation of the first version of Tetris on the Electronika 60 computer.

‍As the next release in Digital Eclipse’s acclaimed Gold Master Series, Tetris Forever includes over 90 minutes of all-new documentary footage exploring the lifelong friendship and creative partnership between Tetris creator Alexey Pajitnov and The Tetris Company founder Henk Rogers, as they share the extraordinary but true story about Tetris.

‍And as this celebration wouldn’t be complete without an all-new Tetris experience, prepare to enter the… Tetris Time Warp! Up to four players will “warp” between different eras of Tetris in real time to experience a variety of classic graphic styles and play mechanics!