Water Sort gives you two empty vials and never more. Play accordingly

How we got these numbers

Level parameters quoted here are read from the game's own generator, src/lib/watersort/levels.ts, as shipped on 3 August 2026. Every level is generated deterministically from its number, so level 74 is the same board for every player.

The one number that decides the whole game

Look down the empty vials column. It never moves. Easy hands you four colours and two empties. Large hands you eight colours and the same two empties. Everything that makes Large harder comes from the fact that your working space stayed constant while the problem doubled.

This is the single most useful thing to internalise. Water Sort is not a colour matching game with some pouring attached. It is a game about a scarce resource, and the resource is empty space.

Scramble depth is how many reverse pours the generator applies, from level 1 to level 100 within each tier.

Two empty vials is roughly two spare moves of freedom. If both are occupied by parked segments, you have no freedom at all, and most lost levels are lost right there.

The three kinds of pour

It helps to stop thinking about pours as one action and start seeing three distinct kinds, because they have completely different costs.

• A merge: pouring onto a matching colour in a partly filled vial. This is free. It never costs space and it always reduces the number of separate segments on the board. Take every merge that is available before you consider anything else.
• A completion: a merge that fills a vial to four of one colour. Better than free, because it takes a vial out of play and permanently shrinks the problem.
• A park: pouring onto an empty vial. This is the expensive one. You are spending one of your two units of freedom, and you only get it back when that colour finds a home.

Almost every losing position looks the same. Both empties hold a parked segment, no merge is available, and the only legal moves shuffle the parked segments back and forth. The board is not technically dead, but it is out of ideas.

The rule that will fix most of your losses

Never park a segment unless you can name the move it unlocks.

That is it. Before you pour onto an empty vial, look at the vial you are pouring out of and ask what the newly exposed colour underneath can now merge with. If the answer is nothing, you have just spent half your freedom to change the picture without changing the position.

The corollary is that parking is at its best when it exposes a colour that has a large partial stack waiting elsewhere. You spend one empty and immediately convert it into a completion or a big merge, which usually gives the empty straight back.

• Good park: the segment above hides three greens, and there is a vial holding one green with space. Park, merge, complete, recover the empty.
• Bad park: the segment above hides one blue, and every blue on the board is already buried. You now hold a hostage.
• Terrible park: parking a segment when a merge was available elsewhere on the board. Merges never expire in your favour, but empties do get consumed by force later.

Read the board before your first move

Because levels are generated deterministically from the level number, board 74 in Medium is the same board for you as for everyone else. That makes a scan worth the ten seconds it costs, since you are solving a fixed puzzle rather than a random deal.

The scan that pays: count how many separate segments exist for each colour. A colour split across four vials is a colour that will need multiple merges and probably a park. A colour already sitting three deep somewhere is your first completion target. Work the nearly finished colours first, because every completed vial is a permanent reduction in the state space you are searching.

• Count segments per colour. Start with whichever colour has the fewest.
• Identify any colour with three of four already stacked. That is your first completion.
• Identify buried colours, meaning a colour whose segments all sit under something else. These are what your empties are ultimately for.
• Do not open by parking the top of the most cluttered vial. That is the instinct and it is usually wrong, because the most cluttered vial is rarely the one blocking a completion.

How the difficulty actually ramps

Within each tier, the generator raises the scramble depth linearly with the level number. Easy level 1 is built from about 10 reverse pours, Easy level 100 from about 26. Large level 100 is built from about 70.

That matters because scramble depth maps roughly to how many colours end up fragmented rather than how deeply any one colour is buried. High level boards do not have one nasty knot, they have many small ones competing for the same two empty vials. The right adjustment is not to think harder about a single vial, it is to sequence completions so that you are never holding two hostages at once.

Every level in the game is verified solvable by a depth first solver before it is served, and levels that fall under a minimum solution length are rejected. So if a board looks impossible, it is not. It is a board where you have already spent your empties badly, and restarting is cheap.

Restarting early is a skill. Once both empties hold hostages and no merge is live, the position is usually dead. Restart at that moment rather than ten moves later.

Nuts and Bolts is the same game with a different skin

If you enjoy Water Sort, Nuts and Bolts is built on an identical structure: four nuts per bolt, and again exactly two empty bolts at every difficulty, from four colours on Easy to eight on Hard. Every principle above transfers directly.

The one behavioural difference is visual. Stacked nuts read as discrete objects while poured liquid reads as a mass, so players tend to count segments accurately in Nuts and Bolts and estimate them in Water Sort. Counting is the better habit, so it is worth carrying back the other way.

Frequently asked questions

Are all 300 Water Sort levels solvable?

Yes. Each level is generated from a solved state by seeded reverse pours, then checked by a depth first solver under the real pour rules before it is served. Boards that cannot be solved, or that solve too quickly, are discarded and regenerated.

Is level 50 the same for everyone?

Yes. The seed is derived from the tier and the level number, so every player sees an identical board for a given level. That is what makes it worth studying a position rather than restarting for a friendlier deal.

Should I use undo or restart?

Undo when you have made one bad pour and can see it. Restart when both empty vials hold segments that have nowhere to go, because from there the remaining legal moves usually just shuffle the same two hostages.

Does a bigger tier mean more empty vials?

No, and this is the crux of the game. Easy has four colours and two empties. Large has eight colours and two empties. The workspace is constant while the problem doubles.