Pinwheel is a TSS → TSD → PC opener created by Winterfrost. In the first bag you only need Z before S and I, and O before L. It can be built 55.16% of the time with mirrors and 32.22% of the time on one side.

1st Bag

This is the preferred way to stack the 1st bag.

A skim variation can be used if the above setup can't be built.

2nd Bag

The main path for the second bag can always be stacked and has a 95.95% chance of achieving an 8-Line perfect clear, with the two most common solves being able to score a Tetris as well.

If you have a late Z piece, rotate clockwise, softdrop and rotate counter-clockwise twice to get it in place, as shown below.

This field is quite clean and flexible, allowing for a multitude of freestyle follow-up options.

8-Height Perfect Clear

This field has a 95.95% chance of achieving a perfect clear. There are only 9 minimal solutions, however due to the TS/Z you technically only need to memorize 6 different solutions.

67.9%, Save Z

67.9%, Save S

42.9%, Save I

40.9%, Save Z

40.9%, Save S

40.9%, Save O

19.0%, Save I

9.5%, Save S

9.5%, Save Z

Upstack Continuation

This was discovered by Ivan28283 and can be used when you want to upstack for a big attack after the second bag. It is possible to always stack this if you have 180 rotations.

This field has a 73.93% of achieving a 14-line perfect clear with 3 solutions.

Alternate 2nd Bags

These setups can always be used in place of the main path and give higher chances to perfect clear, but require more memorization due to having to solve two different fields.

This setup requires L to come before O to be used and has a 100% perfect clear chance with 11 minimals.

57.6%, Save Z

53.6%, Save S

52.5%, Save S

45.8%, Save S

41.2%, Save O

27.3%, Save O

27.1%, Save O

17.6%, Save T

12.4%, Save S

10.0%, Save T

6.3%, Save I

If you get O before L you can build this setup. It has a 99.80% perfect clear chance with 7 minimals though you also need S to come before L or Z if you're playing a game without 180 rotations.

57.4%, Save Z

57.4%, Save S

49.5%, Save O

36.7%, Save I

30.3%, Save Z

26.7%, Save Z

20.0%, Save I

Perfect Clear After 14 Lines

You can go for this after the L before O 2nd bag.

This can be stacked a majority of the time, however there is a fallback that has a 100% build rate with 180 rotations and a 78.85% chance to achieve a perfect clear for when this cannot be stacked.

This field has a 100% perfect clear rate with only 3 minimal solutions, with each one being able to give you a Tetris.

95.0%, IOLSZJT

86.9%, ISOLZJT

73.3%, ILOZJST

Although this can always be stacked with 180 rotations, certain queues will need a lot of waiting for gravity. If J comes before O you could potentially save time by switching to an alternate build.

This field has a 78.85% chance to perfect clear with only 4 solutions.

69.0%, ISOZLJT

21.1%, ISOZJLT

19.0%, JIZSOTL

10.3%, ISZOLJT

Vertical TSS

Double Triple Double

Discovered by mLurker. This bag can be stacked this way almost every time. It sends the same amount of garbage as Stickspin, although it requires a lot of soft drops.

O before S

S before O