From Hard Drop - Tetris Wiki
 Standard and common acronyms
- TGM : Tetris The Grand Master, used to refer to the series in general.
- TGM/TGM1 : Tetris The Grand Master, the first game of the series.
- TAP/TGM2 : Tetris The Absolute Grand Master 2 +.
- Ti/TGM3 : Tetris The Grand Master 3 Terror Instinct.
- ACE/TGMA : Tetris The Grand Master Ace.
- ARS : Arika Rotation System.
- SRS : Super Rotation System.
- IRS : Initial Rotation System.
- IHS : Initial Hold System.
- GRS : Grade Recognition System.
- TLS : Temporary Landing System.
- TTC : The Tetris Company.
- BPS : Bullet Proof Software / Blue Planet Software.
 Basic Terms
- Main article: Glossary
Appellation standards for Tetris games vary, especially with TGM. To avoid confusion, we list here the basic terms used most frequently when in context with the TGM series. All terms are not yet listed, and the order is still not fixed. If a term is not defined here, it is defined in the glossary and may have its own article.
- Main article: Tetromino
In precise language, a block is an element that fills a single square cell of the playfield, and a tetromino (also spelled tetramino or Tetrimino) is made of four blocks. In common use, a "block" sometimes refers to a whole tetromino. This wiki uses "block" and "tetromino" with the meanings described in the glossary.
Seven different tetrominoes exist, each with a letter name (I, J, L, O, S, T, or Z). Precise language uses the letter names, and some players use the color names.
Each time a tetramino is locked in the playfield, it becomes part of the stack. Building a perfect stack is the very essence of all Tetris games, which means stacking each tetramino in a clean manner without making holes. Several other Tetris games pose stacking challenges, and TGM has its own, such as the '>' shape secret grade.
Garbage is also part of the stack. In Vs. mode, the player receives garbage when the opponent clears more than one line with one tetromino. Garbage appears from the bottom of the playfield and pushes up the current stack. The garbage pattern is a copy of the blocks the opponent player had cleared with the blocks of the line clearing piece removed, with the order reversed from top to bottom.
Garbage also appears in Ti Shirase mode from level 500 to level 999 at regular intervals. The garbage lines, in this case, are generated by copying the bottom-most line.
TGM+ mode also sends periodic garbage that forms a regular pattern.
- Main article: Combo
Line clears with consecutive pieces increase the combo score multiplier. Failing to clear a line with the next piece will reset the combo counter.
When the player clears the whole playfield, the message "Bravo" appears on screen (also known as "All Clear"). Bonus points are awarded by multiplying the points scored on a "Bravo" by four.
Before becoming a game, Tetris is basically a program. The frame is the shortest quantum of time in TGM. Like other games made for the Japanese market, TGM runs at a fixed rate of 60 frames per second. A lot of technical concept analysis use the frame as scale value instead of seconds.
Here is the basic of the gameplay process instruction order in ONE frame (draft) :
- Read input
- If piece is active:
- If in Ti or ACE, hold
- If this isn't a piece's first frame, shift (horizontal movement)
- Process delays
- Update the screen and play sounds
Until top out or last level complete
In fact this is very complicated, but just be aware of this general concept, and particularly if you want to learn advanced technique in TGM.
 Lock Delay
- Main article: Lock delay
Unlike in early games such as Tetris for Game Boy, when the tetromino falls onto the stack, it doesn't lock immediately because a short delay still allow you to move it. Lock Delay is visible to the darkening of the tetromino. This feature is necessary as speed increases and critical when reaching 20G. The delay is expressed in frames and the tetromino automatically locks when reaching zero. Lock delay resets each time the tetromino drops one or more steps. SRS also resets Lock Delay when the tetromino is moving and rotating. TGM1 Lock Delay is fixed to thirty frames (~0.5sec) and diminutive as gameplay speed increase on sequels. You can also cancel the Lock delay by pressing Down.
 Initial Rotation System (IRS)
- Main article: Rotate#IRS
The level shows the game's progress. Starting from zero, the level increases by one each time a tetramino is distributed, and by the number of completed rows. On average, it increases by 3.5 for each completed row (however see "Level Step" below). If you are a beginner at TGM, the level is the best information to see your performances progress, rather than the chronometer.
 Level Step
The Level increment can stop when reaching a Level Step (typically _99 : e.g. 99, 199, 299 etc...). You can pass only by completing a row. Each time you pass a Level Step, the game displays a new background. TGM3 also plays a bell ringing sound each time you are close to the Level Step.
 Grade Recognition System (GRS)
ARIKA rewards a player's skill and performance by grade attribution and divides them into class. For example, here is the sorted grade list for the TGM1 unique game mode :
9, 8, 7, 6, 5, 4, 3, 2, 1, S1, S2, S3, S4, S5, S6, S7, S8, S9, Gm.
Becoming a Gm Class player in TGM1 will require much motivation and perseverance even if comfortable with Tetris games in general. The difficulty in obtaining the Gm grade in TGM2 increases even further. It is speculated that there are approximately 10,000 Gm class players in Japan on TGM1 and no more than 100 Gm players in TGM2 Master Mode. In TGM3, The GM grade was widely believed to be impossible to obtain through normal play, but the Japanese Tetris player 'jin8' finally attained GM on July 28, 2007.
A Synchro move is the act of sucessfully inputting both rotation and movement during the same frame. It is commonly executed by loading DAS and using IHS during ARE. Although less useful in low gravity, it becomes essential at 20G for enabling tricky tetramino movements and placements. Synchro moves are not possible under SRS due to the order in which gravity and rotation are processed in each frame.
- Main article: Zangi-move
Zangi-Moves are an original ARIKA technique introduced in TAP made possible by the Sonic Drop feature. To perform the move, you press Up to drop the piece, Left or Right to move the piece over, and Down to lock the piece in place. These 3 inputs are performed with a single circular motion of the arcade stick. This is particularly useful when you are playing for time attack, as you save a significant amount of time by not having to return the stick to its neutral position. Zangi-moves are not possible with SRS.
This move is most useful for tucking pieces underneath overhangs, an operation that costs much time in most other Tetris games. However, it is also used in other situations where the speed gain is more subtle. If you wish to place a piece 1 space away from the spawning location, you will do so with a half circle Zangi-Move. If you want to place a piece 1 space away from a wall, you will use DAS to get to the wall quickly, and then you will use a Zangi-Move to place the piece, all in one continuous 3/4 circle Zangi-Move.
 Word Origin
The word 'Zangi' comes from Zangief's (Street Fighter II) Spinning Pile Driver move, which requires stick rotation and feels similar.
The following animations just show Zangi-Moves example and don't follow an optimized stacking behavior.
- Main article: ARE
- Main article: Torikan
Torikan refers to a condition in TAP and Ti where the game reaches a premature end when the player failed to fulfill a certain requirement up to that point.