Tetrion

The tetrion is the frame that surrounds the playfield. Henk Rogers has defined "tetrion" as the machine that plays Tetris.

Different tetrions may implement different variations of the game rules. For example, TAP indicates the game mode with different frame colors:

In Tetris Worlds, tetrions are described as gateways which, when opened, give the Minos access to a new planet in their galaxy suitable for terraforming.