Tetris is a puzzle game for the Game Boy released in 1989 in Japan and North America and 1990 in Europe. It was developed and published by Nintendo (with the rights to a Game Boy version sub-licensed from Bullet-Proof Software) and is directly based on Alexey Pajitnov's original rendition of Tetris. The basic gameplay involves stacking a series of blocks to create full rows with increasingly fast speeds. This simple gameplay, combined with its basic visuals, gave Tetris a universal appeal that made it immensely popular. It massively helped sell the Game Boy by virtue of being bundled with it upon release.
The goal of the game is to stack blocks into complete lines, removing them from play. All of the blocks, called Tetriminos, are based on the tetrominos (every geometric shape that can be created from four perfect squares). As play begins, a random Tetrimino falls to the bottom of the screen, and the player can position it and rotate it without being able to move it back up. After one is placed down, another appears, and this continues for every subsequent Tetrimino. In single-player, the player can choose from the A-Type or B-Type modes to play. In A-Type, the player selects the speed at which the Tetriminos fall, then the game begins. It continues forever until the Tetriminos reach the top of the screen, with no more room left for them to appear. In B-Type, the player must clear twenty-five lines, and in this mode, they can choose both the Tetrimnos' falling speed and the number of misaligned blocks that are already on-screen. Once the necessary lines have been cleared, the player is scored on their performance. If they complete B-Type with the maximum settings, a special ending plays featuring the launch of a spaceship.
Multiplayer features only two players, and pits Mario against Luigi as they stack Tetriminos on separate fields. If one player clears more than one line, extra lines suddenly appear at the bottom of the other player's screen. Play continues until either one player runs out of space or one player clears at least thirty lines, at which point Mario and Luigi are seen celebrating or moping. The games then begin anew, with a cleared screen, until one player wins three times.
Rogers convinced Arakawa by saying that Tetris would appeal to everyone, whereas Mario would only appeal to kids. As he put it, "[i]f you want little boys to buy your machine include 'Mario,' but if you want everyone to buy your machine, include 'Tetris'".
The popularity of Tetris was immense, to the point where the success of the Game Boy is often attributed to Tetris itself. In no small part because the game was bundled with the Game Boy, it sold over 33 million copies, and its combined earnings was billions of dollars. The game has thus gained a reputation as the handheld's "killer app". Although the game succeeded with Nintendo's core demographic of young children, the game was notably popular with people outside of their usual audience, such as businessmen and other non-traditional gamers, and Nintendo began marketing the game towards them.
Tetris holds the distinction of being the first video game played in space, by Russian astronaut Aleksandr Aleksandrovich Serebrov. The astronaut received the game from Nintendo's then-chairman, Howard Lincoln, while the latter was on a trip in the USSR to see Pajitnov.