>>18
Anything that doesn't play by the game boy rules is unplayable for me. Tetris rule variants are a ridiculously complex topic, but basically the most important issue is that there are many different rotation systems, and some of them make game-breaking moves perfectly legal.
The current "official" implementations are a real joke. It hurts to see the holding company, which no longer has any ties with Pajitnov, assraping our cultural heritage to make it more "casual". Young kids growing up with these versions must have a really hard time understanding why we love this game.