This list is going to be huge, so we should build it carefully. I suggest 3 general categories:

1. Official Tetris Games 2. Official Unrelated Games (games that use "Tetris" or "-tris") 3. Unoffical, Though Significant Fan Games (tetrinet etc.)

To clarify, I think Official Games should include even games that are technically unlicensed, but were believed to be legitimate by the developers. eg. Tengen Tetris & Megadrive Tetris