Tetra Online is a multiplayer fan game by Tetra Dev Studio, inspired by Puyo Puyo Tetris. The game was removed from Steam on December 9, 2020, due to a DMCA notice filed by The Tetris Company.
Tetra Online is a Guideline-based game that has three standard single-player modes and one multiplayer mode.
- Endurance: Standard 150-line Marathon mode.
- 40L: Time attack mode.
- Score Challenge: 2-minute score attack mode.
- Versus: Standard 1v1 multiplayer mode with garbage line attack system.
Tetra Online uses a modified version of SRS, in which the kick tables for the I piece are mirrored from the left side. This allows for symmetrical wall kicks similar to Tetris The Grand Master 3 Terror-Instinct; however, the way the kick table is mirrored allows several situational placements that are impossible in regular SRS to be executed effectively.
||As in Guideline SRS, the shown placement can be achieved by rotating clockwise.
||In the symmetric position, this can now be achieved by rotating clockwise or counter-clockwise.
||Likewise, this placement is possible in the symmetrical kick system where the regular SRS would fail to execute.