OPENERS · LESSON 2 OF 6
TKI
AFTER THIS GUIDEYou can identify the common TKI base and use the upper pieces to distinguish three continuation shapes.
Learn the shared base before the variants.
TKI aims for a T-spin Double in the opening bag. The familiar base uses an early horizontal I. Getting the low support in place before the pieces above it is the key order constraint; holding a piece can help, but not every delayed-I start uses the same route.
Fonzie, flat top and castle top refer to familiar variations in the upper structure, especially the J placement. They are choices about the next board as well as the first Double. Flat top is often used as a bridge towards LST. Fonzie commonly accommodates a late J. Castle top needs O placed before J in the usual orientation.
These are recognition cues, not a complete table of every compatible opening order. The trainer includes alternative routes. Watch which route your current pieces support rather than forcing the first target you memorised.
After the first TSD, return to ordinary queue reading. A second spin, Perfect Clear attempt or simple stack is a decision about the new pieces. The opener name does not choose it for you.
Compare the upper J while keeping the base in view
Fonzie-style reference
Study the trainer’s default first-stage target. Locate the I base, the two clearing rows and the J on the upper right. The picture includes the finishing T; it is not a drop-order instruction.
Flat top
Compare the alternative with a horizontal J across the upper middle. Ask what supported landings this flatter top leaves after the first clear.
Castle top
Find the higher J on the right in the castle target. Note what has to support it. If O has not been placed when it is needed, do not seal its space and hope to insert it later.
Play through one verified bag sequence
This is one supported reference route under the TETR.IO profile, not a prescription for every bag. Advance one locked piece at a time; each picture shows the board after any line clear. The practice mode may generate a different compatible sequence.
Start on an empty board. First bag: O → I → S → L → Z → T → J. Hold starts empty.
1. Place O. No line clear.
2. Place I. No line clear.
3. Place S. No line clear.
4. Place L. No line clear.
5. Place Z. No line clear.
6. Place T. 2 rows cleared; the picture shows the result.
7. Place J. No line clear.
Common mistakes
Memorising only where T finishes
The other pieces make both the spin and the next board. Check their supporting relationships.
Calling every late-I order impossible
There are alternative TKI routes, but they are different constructions. Use a verified route rather than improvising a blocked version of the early-I base.
Forcing LST after every first Double
Flat top can support that transition; the next pieces still have to build it. Take a simpler continuation if they cannot.
TAKE IT TO THE BOARD
Recognise the route before finishing
- Open Openers and select TKI. Set Gravity Off and NEXT 5.
- During three attempts, compare the displayed target with the reference shapes. Name the upper J position before placing it.
- Complete the TSD using the suggested route when needed. At the finish, describe one useful landing on the remaining surface.
What counts as progress? You distinguish base construction from continuation choice and can explain the supporting piece order.
Open practice ↗Opens the mode. Set Gravity and NEXT yourself; your current settings are kept.
Keep these terms nearby
NEXT IN THIS PATH
DT Cannon
Read the setup, its dependencies and its continuation.
Read the next guide →Further reading
For setup variations and additional examples, see FOUR: TKI variants. The practice task here is original to Stacking Lab.