Tetris (Game Boy)

The Game Boy version of Tetris is a very famous rendition and the system's pack-in game for American consumers. The game was so popular, it led to the Game Boy being a major success for Nintendo.

Revisional Differences
Version 1.0 was only released in Japan as part of a Special Link Bundle, and is estimated to have sold around 25,000 copies. Version 1.1, used for the rest of the print run and released internationally, contains the more widely-recognized A-TYPE music and is overall a slightly more polished game.

Copyright Screen
Hyphens were added between "Bullet" and "Proof". Also, the copyright screen is displayed for just two seconds in v1.0; this was extended for v1.1 to eight seconds, although pressing Start after four seconds will take you to the title screen.

Music and Sounds
The A-TYPE song in v1.0 is Minuet. For v1.1, the tune changed to Korobeiniki, which essentially became the Tetris theme.

The "level-up" sound was changed from a simple beep to a short jingle.

Version 1.0 has an unused level-up sound, which can be activated (replacing the normal sound) by using Game Genie code when leveling up.

Level 9
Version 1.0 requires you to score 20 lines on Level 9 to proceed to Level 10. Bizarrely, this was changed for v1.1 to 100 lines.

Block Rotation Glitch
Version 1.0 lets you rotate a block while clearing a line, multiple lines, or a Tetris if there is room in the playing field.