Tetris The Grand Master 3 Terror-Instinct

Tetris The Grand Master 3 Terror-Instinct, abbreviated TGM3 or Ti, is a Tetris brand tetromino stacking game from Arika, part of the TGM series.

Easy
Easy mode has many similarities to the Normal mode of TGM2. It is designed to bring less experienced players into the game who may be intimidated by the high speeds and steep learning curve of Master mode and Shirase. Easy mode is cleared simply by reaching level 200. Play continues during the credit roll as usual and the player's performance is rewarded by fireworks at the end.

Master
Master in TGM3 behaves very much like its predecessor in TGM2. Notable differences include the addition of a hold piece and extra wall kicks for T and I pieces in certain situations. At first, these additions may make TGM3's Master mode appear easier than in TGM2, however this illusion is soon dispelled by a huge increase in speed which will cause all but the most experienced of players to struggle at later levels. The invisible challenge during the credit roll is back in TGM3, however unlike TGM2, surviving this will not award the player a Gm (Grand Master) grade. Instead, "MasterM" is awarded rather than Gm and it is unclear what the Gm requirements are. Many players believe that the explanation for this, is that no GM grade in fact exists in TGM3, although this has not been officially confirmed.

Shirase
This mode follows in the footsteps of TA Death in TGM2, however the immense speed difference is immediately apparent, and continues to increase throughout. Shirase mode does not stop at level 999 as in TA Death and Master mode, and play continues right through to level 1300. Shirase also has other key features:

From level 500 to 1000, a line of garbage identical to the bottom row will spawn at regular intervals.

From level 1000 to 1300, every tetris piece that spawns is colourless and made up of [ ] blocks.

Grading is handled differently in Shirase mode and it is not believed to have an attainable Gm grade. Instead, the game will award an S grade equivalent to the number of sections cleared; the highest grade being S13 for clearing level 1300.

The Shirase credit roll is a 20G, big piece challenge (all pieces are twice their normal size).

Scoring
Unlike in TGM, TGM2, and TAP, TGM3 advances the level further for a 3- or 4-line clear: