From Hard Drop - Tetris Wiki

Stable TST (ステーブルTST) is one of the ground TST openers. This opener was invented by Aotaku1039.

Contents 1 1st bag 2 2nd bag 3 Derivation 3.1 TST 1 3.1.1 8-lines PC route 3.1.2 T-Spin route 3.2 TST 2 4 Other 4.1 6-lines PC 4.2 14-lines PC (Infinite PC-Loop) 5 Reference

1st bag

J>L

J>L

L>J

L>J

You can always stack. If the S-piece is earlier than the Z-piece, use the mirrored shape.

2nd bag

TST 1

TST 1

TST 2

TST 2

You can always send a TST. There are two forms, with "TST 1" going for an 8-lines PC and "TST 2" going for a T-Spin in the 3rd bag.

Derivation

TST 1

8-lines PC route

36.43%

33.65%

30.08%

18.33%

18.33%

15.56%

14.92%

12.70%

11.43%

11.11%

9.52%

8.89%

8.89%

8.25%

6.98%

6.67%

6.67%

5.71%

5.40%

4.76%

4.76%

PC rate is 90.56%. TSD may be sent.

T-Spin route

3rd bag TSD

4th bag TSD

You can always stack both bags.

TST 2

L>O

O>L

You can always send a TSD.

Other

6-lines PC

O-Hold

O-Hold

2-lines PC

DPC-Z

Since the O-Hold TST rate is 33.33% and the PC rate after that is 2.38%, there is a 0.79% chance of sending a PC. However, if successful, a 2-lines PC can always be sent. After that, DPC-Z can be stacked.

14-lines PC (Infinite PC-Loop)

2nd bag TST 1

3rd bag TSM

4th bag TSD (Tetris may be sent.)

5th bag PC

41.83%

41.83%

32.22%

27.78%

27.78%

24.44%

24.44%

19.05%

14.29%

You can always stack everything from the 1st bag to the 5th bag PC, so you have an infinite PC-Loop with just this opener.

Reference

• [Tetris Opener Organizing Wiki]