This is a tetris game written in javascript without using a single image. It requires Firefox browser.
The point of the game is to score as much as possible. Fast play is favored.
By dropping figures (with space) one can get many points - score for droping is proportional to the number of lines the figure falls. Speed increases with time and not with score.
To restart just press F5. To pause press Pause/Break button or P.
To control block's position use left and right buttons, a and d or h and l. To rotate figure press up button, w or j. Ctrl+up or Shift+w(j) rotates clockwise.
To lower figure by one level press down arrow, s or k. It is recommended though to drop figures with space as it's faster and yields significant amount of score.
Older version is also available