Tetris The Grand Master

Tetris: The Grand Master is the first arcade game in Arika's TGM series.

Speed
ARE is fixed at 30 frames (500 ms); DAS is fixed at 15 frames (250 ms) delay, 60 Hz rate.

The speed level is an integer from 0 to 999. Every time a tetromino locks, except at the end of a section (99, 199, 299, ..., 899, 998), the speed level increases by 1. Every time a line is cleared, the speed level increases by 1; this is the only way to finish a section.

Translation from speed levels to gravity

 * This table is approximate, based on various sources on the web. We are seeking a more experienced TGM player to edit this section with more accurate values.

The player can force constant 20G, by pressing ↓↓↓↓ ↓↓↓↓ C B A before starting the game. Unlike TGM2, the lockdown time, spawn delay and DAS time does not change throughout the game.

Scoring and grades
Here is a more technical description of the scoring formula :

Score = Ceil((Level + Lines)/4 + Drop) x Lines x Combo x Bravo

Where: (source)
 * Level is the current level you are on.
 * Lines is the number of lines you just cleared.
 * Drop is the number of spaces you dropped the piece. The last space your piece falls does not contribute to this, however locking the piece once it has landed will add 1 to the Drop.
 * Combo returns to 1 by default every time a piece does not clear lines. Otherwise, it is :
 * Combo = Combo - 1 + (2 x Lines - 1)
 * Bravo is equal to 4 if this piece has cleared the screen, and otherwise is 1.

When the player surpasses a given score, TGM assigns the player a grade corresponding to the score. As in the game Go, grades are "signed":

To achieve Grand Master rank, the player must reach grade 1 before level 300, grade S4 before level 500, grade S9 before level 999, and level 999 at or 13:30:00.