TETERI
Rules and mechanics
Lock Delay: The Half-Second That Saves Your Run
A landed piece does not lock immediately, and nudging it restarts the clock, up to a limit.
When a piece lands it does not lock instantly. You get a short grace period, half a second in TETERI, before it fixes in place.
Why the delay exists
Without it, the game is unfair at speed. At high levels a piece can travel several rows in the time it takes to press a key, and a placement you had correctly planned would be stolen by a frame you could not react to. Losing to your own bad decision is the game working; losing to input latency is not.
The delay makes the last moment of a placement usable. You can slide a piece along the surface it just landed on, or rotate it into a tuck, after it has technically already arrived.
Move reset, and its limit
More than that: moving or rotating a grounded piece restarts the timer. That is what makes last-instant adjustments possible. You are not racing a fixed half-second, you are extending it with each nudge.
Left unbounded, this would break the game entirely. You could shuffle a piece left and right forever and never lock, stalling indefinitely at any speed.
So there is a cap: fifteen resets per piece. After that the timer runs to completion regardless of what you do. Fifteen is generous for real play and tight enough to make stalling pointless.
What it feels like at high levels
At level fifteen, gravity is so fast that a piece is effectively teleporting downwards. Lock delay becomes the only window in which you exist. Skilled fast play is largely about using it: get the piece roughly right on the way down, then do the precise work in the grace period.
This is why high-level play looks like a pause-and-snap rhythm rather than a smooth descent. Players are spending their reset budget deliberately.
The visual cue
TETERI pulses the active piece brighter as its lock timer runs down, so the remaining grace is visible rather than something you have to feel. When it flashes rapidly, you are out of time and out of resets.
Read next
- The Super Rotation System, ExplainedFour defined states per piece and a table of fallback offsets, which is what lets a piece spin into a gap it should not fit.
- Wall Kicks: Why Your Piece Moved When You Rotated ItA blocked rotation tries a list of nudges before giving up. Knowing that list turns a quirk into a tool.
- The Ghost Piece and Why It Is Not CheatingThe outline showing where a piece will land removes arithmetic, not difficulty.
- How the Hold Slot WorksPark one piece for later, but only once per piece, which is what makes it a decision rather than an undo button.
- The Nine-Column Stack and the Open WellFill nine columns flat, leave one open, and wait for the long piece. The standard shape for a high score.
- How to Practise DeliberatelyPlaying more runs is not practice. Constraining a run so it isolates one skill is.