Sorter: Build the Line

#logic#puzzle#machine#sorting#build

How to play

Tap a palette piece, then tap a grid cell to place it. Tap a placed piece to flip its direction. Hit Run to release the balls. Desktop and mobile.

About Sorter: Build the Line

Sorter: Build the Line is not a sorting puzzle so much as a machine-building one. You lay out ramps and colour splitters on a grid, press Run, and then watch a flood of balls pour through whatever contraption you have built, hoping each one ends up in the right bin.

The distinction matters. In most sorting games you make the moves yourself, one at a time, and can correct course as you go. Here you make every decision up front and then have no input at all — the machine either works or it does not, and watching it fail tells you precisely which piece was wrong.

Splitters are the interesting component, sending colours in different directions and letting one path serve several bins. Ramps carry balls across the board. Between them you are solving a routing problem: every colour needs a continuous path from where it enters to the bin that wants it, and those paths share the same limited grid.

The failure mode that teaches the most is the near miss — a machine where three colours land perfectly and the fourth trickles into the wrong bin. That is usually one flipped piece away from working, and flipping a placed piece is a single tap.

Because Run is repeatable and nothing is lost by trying, the loop is quick: build, run, watch, adjust. Tap a palette piece then tap a grid cell to place it, and tap a placed piece to flip its direction. Runs in the browser on desktop and mobile with nothing to install.

Frequently asked questions

How do I play?

Place ramps and colour splitters on the grid to build a sorting machine, then press Run to release the balls. Each ball follows the paths you built, and the aim is for every colour to reach its matching bin.

Can I change my machine after pressing Run?

Not while it is running — you build the whole machine first and then watch it work. But you can adjust and run again as many times as you like, so watching where a ball goes wrong is how you find the piece that needs changing.

How do I place and flip pieces?

Tap a piece in the palette, then tap the grid cell where you want it. Tapping a piece that is already placed flips its direction, which is often all a near-working machine needs.

What do splitters do?

Splitters send different colours along different paths, which lets a single route serve several bins. They are the key to solving levels where multiple colours have to share limited grid space.