C-Spin

The C-Spin (TKI積み) is a kind of Triple Double Attack. It is invented by TKI. This name is given because of the "C" shape that is formed by the J and L. As the name suggests, it results in a T-Spin Triple which is usually followed by a T-Spin Double within three bags. As an opener, it is most often built with an ZST core whereas L and J are used to build the overhang.

Second and later bags
For the TOJ and ITS Cores, the placement of the second bag is fixed while for the ZST Core, it is stacked ad-lib. However, if it is used for Perfect Clear continuations, then case differentiations are present.


 * ZST Core: There is no fixed way of stacking the second bag, so you stack ad-lib. However, you can place the Z piece, it will stabilize the stack. Below is an example with a Trinity followup in the third bag.




 * TOJ Core: The O and Z pieces can always be placed in one of two ways.


 * ITS Core: There are three distinct products made from this setup. One can always stack the second bag depending on the placement of JO in the first bag. In the third bag, a T-Spin Triple or Imperial Cross is possible, depending if O precedes S or vice versa.

ZST Core
This continuation is discovered by the player Chopin. If you can get a flat 6-high-mino stack, you may have a chance to trade the T-Spin Double for a Perfect Clear.

If you cannot execute a Perfect Clear after 6 lines, there still may be a chance of a PC after 8 lines (75.67% PC rate). If that also fails, it can be continued with a T-Spin Triple, Imperial Cross, STMB Cave or a T-Spin Double.

TOJ Core
You may assemble the C-Spin Perfect Clear using the TOJ Core, given the two continuations.


 * O → ZL (95.00% PC rate, 23 solutions): This form has better Perfect Clear solutions than the ZST Core C-Spin since the chance of doing a T-Spin Double before Perfect Clear is significantly better.


 * L → I (94.09% PC rate, 23 solutions)

TZJ Core
Here is another way of stacking the first bag. This will always work if the I piece comes early, although TKI 3 is more appropriate for that dependency. The J piece is in the hold.

This pattern has many continuations depending on the piece order of the second bag.


 * S → LO → Z (96.90% PC rate, 12 solutions): The S piece can be placed even if you have placed OLZ.


 * ZO → L → S (93.02% PC rate, 10 solutions)


 * O → ZL, S → I (91.19% PC rate, 7 solutions)


 * S → Z → O (89.33% PC rate, [http://fumen.zui.jp/?D115@zgg0zhB8glRpi0R4B8glRpB8R4C8hlB8ywH8wwG8Je?AgWTAzCQ9AgngHBg3CwBA+TWCvPdBAzgRpilB8h0AtRpglR?4B8g0BtB8R4C8g0AtB8ywH8wwG8JeAAPTAT7f2AgngHBg3C?wBA+jFDKHkBAzgRph0AtB8ilRpg0BtB8glR4B8g0AtC8R4B?8ywH8wwG8JeAAPTAT43UBgngHBg3CwBA+jFDKHkBAzgzhAt?B8ili0BtB8glR4B8g0AtC8R4B8ywH8wwG8JeAAPTAyCIOBg?ngHBg3CwBA+jFDqSdBAzgzhAtB8glRpi0BtB8glRpB8g0At?C8hlB8ywH8wwG8JeAAPTAyCIOBgngHBg3CwBAOMgC6PdBAz?gilR4B8i0glzhB8Rpg0B8R4C8RpB8ywH8wwG8JeAAPTAxCo?ABgngHBg3CwBA+CMCqyzBAzgilR4B8h0AtglzhB8g0BtB8R?4C8g0AtB8ywH8wwG8JeAAPTAxCoABgngHBg3CwBAuzPCpyz?BAzgilRpB8g0R4glBtRpB8i0B8BtC8R4B8ywH8wwG8JeAAP?TAx/35AgngHBg3CwBAuzPCvyzBAzgg0BtRpB8ili0RpB8gl?R4B8BtC8R4B8ywH8wwG8JeAAPTAR+HOBgngHBg3CwBA+bgC?qiDCAzgzhAtB8glRpywBtB8glRpB8h0C8hlB8wwg0AtH8g0?G8JeAAPTAR4nABgngHBg3CwBA/TFDUXdBAzgQ4zhB8glRpR?4ywB8glRpB8h0C8hlB8Q4g0wwH8g0G8JeAAPTAR4nABgngH?Bg3CwBA/DxCTXdBAzgzhAtB8ilywBtB8glR4B8h0C8R4B8w?wg0AtH8g0G8JeAAPTAR4nABgngHBg3CwBAvjFD0SdBAzgQ4?i0AtB8glRpR4whBtB8glRpB8whAtC8hlB8Q4whg0H8whG8J?eAAPSAYFrAAFrvAAlsKBApyaFDz/AAAzgQ4ywAtB8glRpR4?wwBtB8glRpB8h0C8hlB8Q4g0AtH8g0G8JeAAPSAYlmAAFrv?AAlsKBAqiLuCvOBAAzgRpilB8h0AtRpywB8g0BtB8R4C8g0?AtB8R4wwH8glG8JeAAPSAX1xAAFrvAAlsKBAz3/wCvCBAAz?gzhAtB8glRpi0BtB8glRpB8R4C8hlB8R4AtH8g0G8JeAAPS?AX1xAAFrvAAlsKBAzizPCP+AAAzgg0ywAtB8glRpi0BtB8g?lRpB8R4C8hlB8R4AtH8wwG8JeAAPSAX1xAAFrvAAlsKBAzi?rgCqOBAAzgQ4zhB8i0R4ilB8Rpg0B8glAtC8RpB8Q4BtH8A?tG8JeAAPSAWF0AAFrvAAlsKBAaHstCK+AAAzgQ4ywAtB8i0?R4glBtB8Rpg0B8glAtC8RpB8Q4hlH8wwG8JeAAPSAVVtAAF?rvAAlsKBAviLuCqOBAAzgQ4ywglB8h0AtR4ilB8g0BtB8Rp?C8g0AtB8Q4RpH8wwG8JeAAPSAVVtAAFrvAAlsKBAv3ntCsO?BAAzgQ4zhB8h0AtR4ilB8g0BtB8RpC8g0AtB8Q4RpH8glG8?JeAAPSATV2AAFrvAAlsKBAv3ntCM+AAA 21 solutions])


 * L → O, I → Z (89.25% PC rate, 12 solutions)


 * I → L (88.02% PC rate, 11 solutions)


 * S → L, OI → Z (80.00% PC rate, 8 solutions)