Tetra Online was a fast-paced puzzle stacker. The game required quick reflexes, with the ability to adapt to situations being essential. There were many modes to play, including singleplayer and multiplayer modes. Originally launched as a free-to-play Steam game, Tetra Online, as it was called, was taken offline due to a DMCA notice filed by The Tetris Company on December 9, 2020. The latest source code and binary were made available through GitHub, as development was officially ceased on the project.