PC-Spin (Okey Version) is an Opener resulting in a T-Spin Triple in the second bag, followed by a T-Spin Single or a T-Spin Double in the third bag whereas there is also a good chance to finish this bag with a Perfect Clear.
The Setup (first two bags)
This setup was proposed by the player Okey_Dokey and it resembles the 8th row version of PC-Spin whereas that name originates from a wordplay between PC, short for Perfect Clear, and C-Spin, an alternative name for the Triple Double Attack technique. It can be used for both J & L starts as well as J & S starts and is thus a good alternative to MKO Stacking and the standard DT Cannon opener. The first bag is stacked in exactly the same way as in the standard 8th row PC-Spin setup - except for the I piece which is placed vertically one column away from the left wall. In the second bag the player must pay attention to the order in which the O and J pieces show up. In any case, a T-Spin Triple is executed at the end of the second bag which immediately prepares a T-Spin Single for the third bag.
If O comes before J, then the second bag can always be stacked like this (this is the preferred way):
And if J comes before O, then the second bag can always be stacked like this (it may require a J-Spin if J comes after S and T):
O before J (third bag)
The case O before J offers a 95.9 % chance to get a PC in the third bag, or 71.2 % if requiring a T-Spin Single beforehand (and 48.7 % if requiring a TSD).
The 71.2 % chance for TSS -> PC can be achieved by using these 14 PC solutions (all solutions):
If the T piece shows up among the first 2 pieces of the third bag, then it's always possible to achieve a PC after starting the bag with a T-Spin Single.
The 95.9 % chance for just PC can be achieved by using these 4 PC solutions additionally (all solutions):
Here are some placements of 2 pieces that guarantee the Perfect Clear - no matter in which order the other pieces show up. There's a 38.10 % chance that one of these can be applied (or 9.5 % if requiring a TSD additionally). (all 2-piece placements)
Here are some placements of 3 pieces that guarantee the Perfect Clear - no matter in which order the other pieces show up. If including the placement of 2 pieces from above, then there's a 55.5 % chance that one of these can be applied, or 47.9 % if requiring a T-Spin Single additionally (or 20.2 % if requiring a TSD additionally). (all 3-piece placements)
Here are some placements of 4 pieces that guarantee the Perfect Clear - no matter in which order the other pieces show up. If including the placement of 2 and 3 pieces from above, then there's a 68.6 % chance that one of these can be applied, or 63.8 % if requiring a T-Spin Single additionally (or 38.6 % if requiring a TSD additionally). (all 4-piece placements)
J before O (third bag)
The case J before O offers a 96.9 % chance to get a PC in the third bag, or 65.1 % if requiring a T-Spin Single beforehand (and 39.0 % if requiring a TSD).
The 65.1 % chance for TSS -> PC can be achieved by using these 11 PC solutions (all solutions):
Note that here the T-Spin is sometimes required to be vertical, in which case either J piece or L will stay on hold instead of S, Z, O or I.
The 96.9 % chance for just PC can be achieved by using these 9 PC solutions additionally (all solutions):
Here are some placements of 3 pieces that guarantee the Perfect Clear - no matter in which order the other pieces show up. There's a 41.0 % chance that one of these can be applied, or 30.0 % if requiring a T-Spin Single additionally (or 12.1 % if requiring a TSD additionally). (all 3-piece placements)
Here are some placements of 4 pieces that guarantee the Perfect Clear - no matter in which order the other pieces show up. If including the 3-piece placements from above, then there's a 79.2 % chance that one of these can be applied, or 53.9 % if requiring a T-Spin Single additionally (or 30.0 % if requiring a TSD additionally). (all 4-piece placements)
Late T Piece (third bag)
If T piece comes late in second bag, it may be best to ignore the PC solutions entirely, and just stack a little up to get a T-Spin Double with back-to-back bonus. However, the PC solutions with a missing O piece offer an alternative route: Burn some lines, use the O piece to create an overhang, and then perform a T-Spin Double without back-to-back bonus - resulting in an almost empty playfield.
The PC solutions with a missing Z piece can be used in a similar way. However, this creates a hole on the left wall. It may still be useful when receiving garbage with its holes on the other side.
See Also
