The Back-to-Back Bonus, and What Counts as Difficult

Chain four-row clears and T-spins without an ordinary clear between them, and everything is worth half again as much.

Some clears are classed as difficult: any four-row clear, and any T-spin, including minis. Everything else, meaning a single, a double, or a triple without a spin, is ordinary.

Perform two difficult clears in a row, with no ordinary clear between them, and the second and every subsequent one scores 1.5 times as much and sends one extra row of garbage in versus.

What breaks the chain

Only an ordinary line clear. Specifically:

• Placing pieces without clearing anything does not break it. You can build

for twenty pieces and the bonus is still live.

• A single, double or triple does break it, immediately.
• A T-spin that clears no lines does not break it. It is still a difficult

clear.

So the chain is not about tempo. It is about discipline: never take a cheap clear while a difficult one is available.

The arithmetic

At level ten, a four-row clear scores 8000. With back-to-back, 12000. Sustained over a run, that is not a rounding error. It is most of the difference between a good score and a great one.

In versus it matters even more. Four rows becomes five, every time, for as long as you can hold the chain.

The discipline it demands

The bonus punishes exactly the instinct that keeps you alive: when the stack gets uncomfortable, clear something. Taking a single to relieve pressure is often correct, and it costs you the chain.

That tension is the interesting part. Every time you are tempted by a quick single you are choosing between safety now and points later, and the right answer genuinely depends on how high your stack is and what your queue looks like.

Reading it in TETERI

The BACK-TO-BACK badge beside the well tells you the bonus is live. If it is showing, a single will extinguish it. If it is not showing, you have nothing to protect and should take whatever clear keeps you alive.

Read next

• How the Seven-Bag Randomiser WorksPieces are not drawn at random. Every group of seven contains each shape exactly once, which makes the queue countable.
• 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.
• Lock Delay: The Half-Second That Saves Your RunA landed piece does not lock immediately, and nudging it restarts the clock, up to a limit.
• The NES Version and Its Beautiful FlawsNo hold, no kicks, a randomiser that can starve you, and a scoring table that made it a competitive sport anyway.
• Downstacking: How to Dig Yourself OutClearing your way down to a buried hole is a distinct skill, and it is the one that turns bad runs into recovered ones.