This version of Tetris has two modes of play: A-Type and B-Type. In A-Type play, the goal is to achieve the highest score. As lines are cleared, the level advances and increases the speed of the falling blocks. At the beginning of a B-Type game, the board starts with randomized obstacle blocks and the goal is to clear 25 lines. In B-Type, the level remains constant, and the player chooses the height of the obstacle beforehand.[2]
During play, the tetriminoes are chosen randomly. This leaves the possibility of extended periods with no long bar pieces, which are essential because tetrises are worth many points more than lesser line clearings. The next piece to fall is shown in a preview window next to the playfield. In a side panel, the game tracks statistics of how many of each tetrimino appeared.[2]
In A-Type, the level advances for every 30 lines cleared, not 10. Each successive level increases the points scored by line clears and changes the colors of the game pieces.[2] Some levels also increase the speed of the falling pieces. Level 29 has tremendous speed, which may end the game almost immediately and is often called the "kill screen", although skilled players can progress.[3] When starting a game, the player can select a starting level from 0 to 19. When starting on a later level, the level is not supposed to advance until as many lines have been cleared as it would have taken to advance from level 0 to the starting level.[2] Due to a bug, the levels will begin advancing earlier than intended when starting on level 11 or higher.[4]
Saint Basil's Cathedral appears in the title screen and ending, alluding to the Soviet origin of Tetris.[5]
At the end of an A-Type game, a substantial score yields an animated ending of a rocket launch in front of Saint Basil's Cathedral. The size of the rocket depends on the score, ranging from a bottle rocket to the Buran spaceplane. In the best ending, a UFO appears on the launch pad and the cathedral lifts off.[4] After a high-level B-Type game, various Nintendo characters perform in front of the cathedral.
