How to play TETERI

TETERI is a block-stacking arcade game you play in a browser. Pieces fall into a well ten columns wide; fill a row all the way across and it vanishes. Let the stack reach the top and the run is over. That much you can work out in about ten seconds. This page covers everything the game does not stop to explain — what each clear is actually worth, how T-spins work, and why in a duel the best defence is a bigger attack.

The basics

Seven piece shapes come round in a shuffled bag: each set of seven contains every shape exactly once, so a long drought is impossible and you can plan around what has already appeared. The next queue shows what is coming; the hold slot parks one piece for later, and you can only use it once per piece.

A piece that lands does not lock instantly. You get a short grace period, and nudging or rotating it resets that timer — up to fifteen times. This is what makes tucking a piece under an overhang at the last moment possible.

Gravity tightens every ten lines. By level ten the pieces are falling faster than you can comfortably read them, which is the whole game: your planning has to get ahead of the clock.

Controls

A flick down slams the piece; a slow drag down is a soft drop. The difference is speed, not distance, so a deliberate drag will never slam by accident.

Two players, one keyboard

In local versus the keyboard splits by physical key position, so the clusters stay put on non-QWERTY layouts. Player one uses A D to move, S to soft drop, W and Q to rotate, shift to hold and space to slam. Player two uses the arrow keys, / to rotate back, right shift to hold and enter to slam.

Scoring

Every value below is multiplied by your current level, so the same clear at level ten is worth ten times what it was at level one. Clearing rows in bulk is worth dramatically more than clearing them one at a time — four singles score 400, while one four-row clear scores 800.

Soft dropping scores one point per row and a hard drop scores two, which is small but adds up over a long run. A perfect clear — emptying the well completely — is the single biggest swing in the game, and in versus it is usually decisive.

T-spins

A T-spin is the game rewarding you for fitting a T piece somewhere it should not fit. Two things have to be true when the piece locks:

1. The last thing you did was rotate it, not move it.
2. At least three of the four corners of the T's three-by-three box are occupied by blocks or walls.

In practice: build a notch one cell wide with an overhang above it, bring the T alongside, and rotate it into the gap at the last moment. The rotation kicks the piece into place — that kick is what the rules are detecting.

A T-spin double is worth 1200 points against a plain double's 300, and sends four rows instead of one. Learning one T-spin setup will do more for your score than any amount of faster stacking.

Combos and back-to-back

Clearing rows with consecutive pieces builds a combo. Each link adds 50 points × the combo length × your level, and from four links on it adds extra garbage in versus. Break the chain by placing a piece that clears nothing and the counter resets.

Separately, a Teteris and any T-spin count as difficult clears. Two difficult clears in a row, with nothing ordinary between them, score 1.5× and send an extra row. Chaining Teteris to Teteris is the standard way to build a big score, and the badge beside the well tells you the bonus is live.

Versus: attacking and defending

In versus modes your clears become garbage rows in your opponent's well. Garbage rises from the floor with a single gap in it, so it does not just make their stack taller — it makes it messier.

The rule that decides most duels: your outgoing attack cancels incoming garbage first. If four rows are queued against you and you land a Teteris, the four cancel out and nothing reaches either player. Sitting on a defensive stack does not work; the only real defence is a bigger clear.

Incoming garbage waits in the meter beside your well and only lands when you place a piece that clears nothing. That gap is your window: if the meter is filling, do not place a quiet piece — find a clear.

Three ways to duel

• Versus CPU — rookie, pro or nightmare. Nightmare does not make mistakes, so you will have to out-attack it rather than wait.
• Local versus — split screen, two players, one keyboard.
• Online — share a five-character room code. The two browsers connect directly to each other, and both players receive an identical piece sequence, so the match is purely about what you do with it.

Getting better

• Keep the stack flat. A flat stack accepts any piece; a jagged one only accepts a few. Most runs end because the board stopped accepting what the bag offered.
• Do not bury holes. A covered gap costs you every row above it. Taking a worse placement now to avoid a hole is almost always right.
• Keep one well open for I pieces — usually a column at the edge — and stack the other nine flat. That is the standard Teteris setup.
• Use hold as a plan, not a panic button. Parking an I piece until the well is ready beats dropping it flat.
• Watch the next queue, not the falling piece. By the time you are reacting to the piece in play, you are already behind.
• Learn one T-spin setup. It is the highest return on effort in the entire game.

Common questions

Is TETERI free?

Yes — no account, no install, no payment. It works offline once loaded, and you can install it to your home screen from your browser's menu.

Does it work on a phone?

Yes, in both orientations, with gestures and on-screen buttons. Rotate to landscape and the controls move to two thumb clusters at the edges of the screen.

Do I need to download anything to play online?

No. Share a room code and the two browsers connect directly. Nothing is installed and no account is created.

Can I change the controls or turn off the effects?

Screen shake, scanlines, the ghost piece and both volume levels are in Settings on the title screen. If your system asks for reduced motion, the game turns the heavier effects down on its own.

Where is my high score stored?

In your browser, on your device. Nothing is uploaded anywhere. Clearing your browser data clears your best score with it.

Want more depth? The articles cover the history of the genre, the exact rules, advanced technique and how this game is built.