Twists, called "spin moves" in The New Tetris's manual, let a player fix some otherwise difficult situations. These examples cover recent games, but some of them may not work for earlier Tetrisgames that use little or no wall kick.
Some games give scoring rewards for twisting a tetromino into a tight space. Two basic algorithms, with slight variations, have been used in newer games to detect and reward in-place spins:
Immobile, used in The New Tetris: A twist is recognised if a tetromino locks in a position where it cannot move left, right, or up. There is only a reward if rows are completed in this way.
3-corner T, used in Tetris DS and other SRS based games: A T-spin bonus is awarded if all of the following are true:[1]
Tetromino being locked is T.
Last successful movement of the tetromino was a rotate, as opposed to sideways movement, downward movement, or falling due to gravity. (Canceling lock delay in games that allow it, such as Tetris DS, does not count as a movement.) The tetromino doesn't even have to end up in a different orientation than it was dropped in; setting up the "well-known twist" below in Tetris Worlds or Tetris DS and pressing both rotate buttons (B–A or A–B) will trigger the T-spin bonus even without any net rotation.
Three of the 4 squares diagonally adjacent to the T's center are occupied. (In Tetris DS, the walls and floor surrounding the playfield are considered "occupied", while in Tetris Worlds for GBA, they aren't.
3-corner T no wall, used in Tetris Worlds: The walls and floor surrounding the playfield are not considered "occupied". This means that if a wall kick places the T tetromino with its flat side against the wall or floor, the T-spin will not be recognized. (Kicks that place the flat side against blocks in the playfield still work.)
3-corner T no kick, used in Tetris: New Century, iPod Tetris, and Tetris Evolution: The final rotation must not involve a wall kick, that is, it recognizes only the "well known twist" below.
(The names for the algorithms are unofficial, taken from the fan gameLockjaw.)
In some of these diagrams, especially those involving S and Ztetrominoes, the "center" corresponding to the center of rotation in SRS is marked with a circle ().
Twists by tetromino
Twists with T (or T-Spin)
A well-known twist involves the tetromino T. In fact, these are the only twists that games that use "3-corner T no kick" reward.
Soft drop
Rotate left
Soft drop
Rotate once
Or twice
In SRS games that reward kick T-Spins like Tetris DS and Tetris Zone, these twists count towards the score. This one does not count towards the score in games like Tetris Evolution or Tetris Splash.
Soft drop
Rotate right
The following works in Tetris DX, TGM rotation, and SRS, but it is not scored as a T-spin in Tetris Worlds if performed on the floor of the playfield.
Soft drop
Rotate right
The above move must be done differently in The New Tetris, but also works and in games using TGM rotation, but not SRS. As this does not involve a wallkick in TGM, it also works in Sega rotation. This diagram will use TNT colors.
Firm drop
Rotate left
This example from SRS is not a T-spin under the old rule, as the tetromino could have been rotated before being dropped, but SRS games from Tetris Worlds through Tetris Online (Japan) count it anyway:
This one is a T-spin in Tetris DS but not Tetris Worlds due to the difference in how the playfield walls are handled:
Triples may not seem possible, but especially games using SRS will allow them regardless. Notice that the ending position of the T tetromino does not overlap the starting position. Later guideline games don't recognise this, either by not counting triples made with this twist as a T-spin (Tetris Zone), or by not recognising this twist as a T-spin at all (Tetris Evolution).
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