Tetris (Sega)

From TetrisWiki
Revision as of 14:02, 6 January 2019 by Simonlc (talk | contribs)
Jump to navigation Jump to search
Tetris (Sega) flyer.jpg
Platform(s)Sega System 16B
Sega System 16A
Sega System E
Taito H System
Taito B System
ReleaseDecember 20, 1988
Gameplay info
Next pieces1
Playfield size10 × 20
Hold pieceNo
Hard dropNo
Rotation systemSega Rotation (no wall kicks)
This article is about the 1988 arcade version. For the 1999-2000 arcade and Dreamcast version, see Sega Tetris.

Tetris is an arcade game published by Sega in 1988. It took Japanese arcades by storm, and is one of the most commonly known versions of the game. Due to its popularity, it became the base of rules for many other Japanese games created later on, both licensed and unlicensed. Such games include the TGM series, Tetris Plus series, Tetris S and Shimizu Tetris. It was one of the first games to have lock delay, greatly improving maneuverability at high speeds.


Japanese man playing Tetris (Sega)

Sega's version of Tetris is an endless game with the only goal being to score points. As the player progresses, the levels increase thereby changing the game speed. Highly skilled players can play indefinitely, even when the score counter stops at 999,999 points, though players usually stop once this is achieved.

Being an early game, released just one year after Elorg licensed Tetris to publishers, tetrominoes can only be rotated counterclockwise. Unlike these games however, this version has 3 buttons which can be tapped quickly in a piano-like motion, equivalent to a clockwise rotation.

It did not implement wall kicks or hard drop. However, many of the mechanics that exist in later games were first seen in this version, such as 1G DAS movement, lock delay, ARE, and rotation/movement processed before gravity—allowing for synchro moves to be performed at 1G fall speed.

A game design element not commonly seen in recent games is the existence of a ceiling. The playfield height is 20 rows, and any rotation that would exceed that height will fail. At high gravity speeds, players must time their piece rotations so the piece is not touching the ceiling, and also not stuck in the stack.

Power-on Pattern

Main article: Power-on pattern

One characteristic of this version of Tetris was the existence of a Power-on pattern. This referred to the game's behavior that the string of pieces it dealt in the very first game after starting up the system was always the same. This was most probably caused by the state of the randomization seed in the system. After its discovery, players began constructing gameplay plans around the power-on pattern in order to max out the score in the least lines possible. Sega Tetris (1999, Arcade, Dreamcast) pays tribute to the power-on pattern, by dealing the sequence in the final level of the single-player game. Tetris S also contains the pattern.

For MAME players, unless you are playing the bootleg, you must delete your NVRAM before playing to get the power-on pattern. The B-system version has a different power-on pattern, and does not require you to delete your NVRAM. It even restores the pattern upon reset, which not even the bootleg will do. The System E version does not have a power-on pattern.


A TAS for Sega's Tetris abuses lock delay and step reset to keep pieces active until the level timer expires, to level up as much as possible with the fewest lines cleared. At a higher level the points awarded from line clears is greater, thus needing fewer total lines to achieve a maxout.

(TAS) Sega Tetris maxout in 98 lines

Development of Taito H System version

This section needs expansion. You can help TetrisWiki by expanding it.


Speed Levels

There are four difficulties which affect the speed, easy, normal, hard and hardest. The game difficulty can be configured through the DIP switch on the arcade board.

Graph of gravity timings per level
Fall speed table; frames per cell
Level Easy Normal Hard Hardest
0 48 48 40 30
1 32 24 20 15
2 24 18 16 12
3 18 15 12 10
4 14 12 10 8
5 12 10 8 6
6 10 8 6 4
7 8 6 4 2
8 6 4 2 1
9 4 2 1 1
10 12 10 10 8
11 10 8 8 6
12 8 6 6 4
13 6 4 4 2
14 4 2 2 1
15 2 1 1 1

Level advancement requirements

There are two ways to increase the level:

  • Clear 4 lines in any combination of line clears.
  • Place a tetromino after the "level timer" reaches a certain value. (Level will not increase if a line clear happens. [Clarification needed])

The level timer increases every frame, except when reset after line clearing and before level-up is shown.

Level timer per level
Level 0 1-8 9-10 11-14 15-99
Required time (frames) 3480 2320 3480 1740 3480
Required time (Seconds) 58 38.67 58 29 58

Level 15 value is used for levels 16 to 99.


Level Points for
1 line
Points for
2 lines
Points for
3 lines
Points for
4 lines
Points for soft dropping pieces
0-1 100 400 900 2000 1 per line
2-3 200 800 1800 4000 2 per line
4-5 300 1200 2700 6000 3 per line
6-7 400 1600 3600 8000 4 per line
8+ 500 2000 4500 10000 5 per line

If a line clear is also a Perfect Clear, a 10x multiplier is applied to the awarded points.


  • Current piece fall speed is located at C7000Ah in the RAM.
  • Current level timer is located at C72336h (word) in RAM in System 16A version; FFE336h in System 16B version. This table is located at 3D28 in the 68k portion of an unshuffled ROM for System 16B version.

See also