Each falling piece contains at least one bomb. Most contain one bomb, not in a position horizontally or vertically between other blocks (for example not in the center of an L, J, or T), but every eighth piece is made entirely of bombs. When rows of the playfield are filled, they do not disappear as in other games; the bombs within the row explode depending on how many rows are filled at one time. It is possible for rows to be filled with no bombs, which increases the size of the next explosion.
Tetris Blast uses the sticky style of line clear gravity, allowing pieces unconnected to anything to fall. This allows chain reactions.
Whenever a piece enters the playfield, four bombs arranged into the shape of an O tetromino will become a larger bomb. Unlike in The New Tetris, these transformations happen only after the field has settled after explosions and gravity, meaning that large bombs can be formed only in rows that still have a gap. Unlike in Lumines , large bombs cannot be made of overlapping blocks.
This version of Bombliss includes three modes of play. Training allows the player to set the gravity speed, and displays four pieces in the piece preview instead of one.
