Tetris: The Grand Master (abbr.TGM) is a popular variant of the classic puzzle game Tetris. Initially released only in Japan for arcades in 1998, the series eventually came to the Xbox 360 in 2005 under the name Tetris: The Grand Master ACE as a part of the Japanese launch lineup. Developed by Arika and published by AQ Interactive, TGM ACE has more in common with so-called "guideline" Tetris games (such as Tetris Worlds and Tetris DS) than previous games in the TGM series.
Changes to the franchise
ACE abandons the level up system used in previous TGM series games. In other TGM games, the level counter would increase with every piece placed or line cleared, with the exception of the end of each 100 level section where only clearing a line will allow the player to progress to the next. (i.e. a line must be cleared to progress past the "level stops" at levels 99, 199, 299, 399, etc.) In ACE, the main game modes are simply 150 lines long, with sections being 10 lines long as in the level systems of many other popular Tetris games.
ACE also does not prominently feature a grading system in its main game modes -- a feature that was previously a staple of the series. Instead, the main game modes are 150 line time attacks. There are allusions to grading system in its Promotional Exam mode, but the "grades" are individual courses that require completion of certain tasks much like those in Tetris DS's Mission mode (survive x lines under certain gravity/speed conditions, clear the highlighted lines, play for x lines with pieces twice the size, clear x number of tetrises, etc.) rather than evaluations of a single performance. Beyond that, the grades are presented in kyu/dan format rather use TGM's 9->1, S1->S9 grade names, and a TM (Tetris Master?) grade substitutes for the familiar GM (Grand Master) grade. ACE also features a separate mission mode without the grade connotations called Tetris Road.
Earlier TGM series games featured what is commonly known as the Memory 4 randomizer. Memory 4 keeps a record of last four pieces received and will re-roll up to six times before dealing a repeat of a piece contained in the history. ACE instead features the Bag 7 randomizer introduced in Tetris Worlds, which deals out shuffled "bags" of the unique 7 pieces. The consequences of Bag 7 is that no pieces will be recycled within a given bag, forcing a normal distribution of pieces. This substitution of randomization rules leads to a noticeably different feel in the piece sequences generated from previous TGM games to ACE.
One of the most important differences between ACE and other TGM games were changes made to its piece locking rules. The TGM series typically features the "step reset" lockdown rules pioneered in Sega's 1988 arcade Tetris. Step reset gives a limited amount of time after the piece touches the ground before it will lock, with the timer resetting if the piece falls to a lower row. ACE features the "move reset" lockdown rules featured in guideline games such as Tetris Worlds that were critically acclaimed as "broken." In move reset, the timer that forces the piece to lock resets any time the piece is moved or rotated. Although ACE does not allow an infinite number of rotation resets as in Worlds, the number of move resets that are allowed is so high that the limitation makes little difference. The inclusion of move reset greatly reduces the challenge of the high speeds featured in TGM series games.
Although so-called "Super Rotation System" introduced in Tetris Worlds is enabled by default, ACE does allow players to unlock and select the more conservatively and elegantly designed "Arika Rotation System" featured in previous games. While SRS features questionably powerful wall kicks to nudge the piece about if normal rotation fails (enabling maneuvers such as the infamous T-Spin Triple), ARS is based on the rotation rules featured in Sega Tetris and adds only simple wall kicks to nudge the piece one space right or left (or up, but only if the piece is a T or I piece). However, unlike the rotation rule options in Tetris: The Grand Master 3, changing the rotation rules does not change the piece colors to match. Regardless of whether the player selects SRS or ARS, the colors are always the guideline standard; there is no option to enable Sega-based colors for ARS.
Despite the copious changes from previous installments, some of the more important features did survive the cut. As previously mentioned, TGM's token rotation rules are still available despite being stuck with move reset and guideline colors. ACE also still sports key features such as Initial Rotation/Hold Systems (which allow the player to pre-rotate or pre-swap a piece during the short delay before it enters) and 20G (the maximum gravity or "instant drop," where the piece falls all 20 rows of the field in one frame). Like TGM2 and TGM3, ACE also pushes the speed after reaching the maximum gravity by decreasing the lengths of various delays (e.g. how long left/right must be held before the piece starts auto-shifting, the amount of time before a piece locks automatically, etc.). Much like TGM2's Death and TGM3's Shirase, ACE's Another and Another 2 modes start the game at 20G and push the speed with each section completed. Although the difficulty is arguably reduced on account of changes such as move reset lockdown, these modes do the best job of keeping with the spirit of previous titles.
ACE features two multiplayer modes: Versus and Doubles. Versus sends attacks based on the shape and position of the piece used to clear lines as in previous TGM series games, but is set to a curiously short length of 20 lines. Although there is some still some strategy in where one places their attacks, matches are rarely won by topping the other player out. Doubles is a co-operative mode like the one featured in TGM2, where two players are given control of separate pieces in a single, slightly expanded playfield.