T-SPINS · LESSON 3 OF 6
TST and the magic key
AFTER THIS GUIDEYou can distinguish a deep slot from a reachable TST and plan what to do with its leftover roof.
The “magic” is a tested rotation offset.
A T-spin Triple clears three rows with a recognised T rotation. A sideways T spans three rows, but simply drawing its final shape inside a tall cavity does not establish an entry. It must be reachable under the selected rotation system.
When an in-place turn collides, SRS tries a fixed list of offsets called kicks. A typical TST entry relies on one of these offsets moving the T under a ledge and into the deeper cavity. There is no universal magic key that works for every orientation: the approach, turning direction and surrounding blocks matter.
The construction is a larger commitment than a shallow TSD. Before adding height, name the T entry and the piece you will use to repair the overhang afterwards. A successful attack can still leave an awkward board.
Treat the coach’s demonstrated path as a path to inspect. Pause before the final T, observe the rotation direction, and reproduce it slowly. If you mirror the construction, recheck the moves; mirroring swaps J/L and S/Z roles as well as left and right.
Study a kick before committing to a Triple
Compare a blocked turn with its offset
In the verified sequence below, T descends just left of the ledge, moves right once and rotates counterclockwise. The kick places it deeper than an in-place turn could reach. Follow each frame before comparing the general kick illustration.
Separate the approach from the final turn
The right movement brings T beside the ledge; the counterclockwise rotation moves it into the lower slot. This exact route is verified under the TETR.IO profile. Recheck the entry when the surrounding blocks or profile change.
Inspect the exit
After the three rows clear, point to the roof that remains. Choose a reachable cleanup landing before deciding to construct another Triple. A J or L often helps, but the visible queue decides your route.
After descending: the T is just left of the overhang. This shows the lower eight rows.
Move right once to approach the ledge. The T still points upwards.
Rotate counterclockwise once. The SRS kick shifts T into the deep slot, completing three rows.
After locking and clearing three rows, the roof remains. Plan its cleanup.
Turning in place would put one cell beyond the left wall.
The first successful SRS offset moves the rotated T one cell right.
Common mistakes
Hard-dropping before the final turn
Once the piece locks, the rotation opportunity is gone. Use soft drop for the approach and finish the entry before hard drop. With gravity on, lock delay still applies.
Assuming a deeper hole makes a better attack
Height without a verified entry and cleanup plan is a liability. Prefer a simpler clear when the queue cannot finish the structure.
Leaving the roof for later
A dangling overhang can restrict every following piece. Identify it before the clear, not after the next piece gets stranded.
TAKE IT TO THE BOARD
One Triple and one cleanup plan
- Open TST, Gravity Off and NEXT 5. Use the coach to inspect one reachable Triple.
- Before playing T, describe the approach and rotation. Execute slowly, using Undo if you lock too early.
- After the clear, choose a placement that repairs the leftover surface. Complete that cleanup before starting another setup.
What counts as progress? You can reproduce the entry and explain the post-clear repair, rather than recognising only the final T shape.
Open practice ↗Opens the mode. Set Gravity and NEXT yourself; your current settings are kept.
Keep these terms nearby
NEXT IN THIS PATH
STSD and Fractal
Understand two different ways to connect Double to Double.
Read the next guide →Further reading
For setup variations and additional examples, see FOUR: T-spin Triple. The practice task here is original to Stacking Lab.