水排序

Water Sort: rules and solving techniques

Pour colored liquid until every tube contains a single color. This guide reflects the controls and win conditions in the current browser build. It is reviewed by the PocketJoy game-testing team and maintained by Long-Term New Media Limited.

How it works

The screen holds a number of tubes containing mixed coloured liquids, along with one or two empty tubes that provide your manoeuvring space. Tap one tube as the source and another as the destination to pour. Two restrictions apply: the destination must be empty or its top colour must match the source's top colour, and each pour moves the entire run of same-coloured liquid at the top of the source, limited by the space available — if the source has three units of one colour on top and the destination has room for one, only one unit transfers and the other two stay behind. The puzzle is complete when every non-empty tube holds a single colour and is full. The number of colours is adjustable across three settings, and undo is unlimited. After choosing a source the status line prompts you for a destination, and an illegal pour explains why it cannot be made.

Tips for clearing levels

Empty tubes are your only buffer, and using one costs you a degree of freedom, so work out how you will clear it before you commit. Look first for two tubes whose top colours already match and merge them directly, since that costs no empty tube and is the most efficient move available — and merging often exposes a new run of the same colour beneath, producing a chain. To open up a stuck position, find tubes with only a short mismatched segment on top of a solid block of one colour: move that segment away and the tube becomes a usable collection point, which is the central solving idea of the genre. Before starting, count the total quantity of each colour; usually each fills exactly one tube, which tells you how many units a given tube still needs and whether a colour is already fully gathered. A more advanced technique is working backwards: decide which tube will finally hold which colour, normally the one already holding most of it, then reason back about where the other colours must move to make way. When you reach an impasse, check whether an empty tube has been occupied by a stray colour, which is usually the root of the deadlock.

Common pitfalls

The most common mistake is pouring into an empty tube for convenience. Once an empty tube is occupied by a colour that cannot be poured out again, because no other tube is topped with it, the position is often dead — and that deadlock typically only becomes apparent several moves later. The second is deciding a pour by looking at the top unit only, forgetting that an entire run moves at once: if the source has three units of one colour on top and the destination has room for one, only one transfers and the remaining two stay behind, which can wreck your plan, so check both the length of the source run and the destination's remaining space before pouring. The third is neglecting undo. It is unlimited and reaches back to the opening layout, and using it lets you probe safely to see what a pour would produce, turning the game from one where you must think everything through into one where you can think as you go. The fourth is exhausting your empty tubes before completing a single pure-colour tube, at which point the position is almost certainly locked.

Great for

Suited to players who enjoy sorting and turning disorder into order. There is no time pressure, undo and restart are always available, and the process is genuinely relaxing — much of the appeal of this genre lies in offering a completely controllable process of imposing order, something real life rarely provides, with a clear sense of progress at every step. Water sort games appeared and spread rapidly on mobile platforms around 2020 and are one of the few recent genres to have travelled backwards from casual mobile into browser games. They are algorithmically interesting too: the generalised problem is a state-space search, level designers must guarantee that a path from the initial state to the goal exists, and the player is in effect performing a manual depth-first search. With an adjustable colour count, four colours suit a beginner while six require real planning. Rounds are short enough for a few games in a spare moment.

Highlights

Three colour counts are offered — four, five and six — with more colours demanding deeper planning rather than merely adding variety, since each additional colour grows the space of possible states exponentially. The run panel shows your move count and your best result for that difficulty, so a solved puzzle can be revisited as a challenge to use fewer moves. Undo is unlimited and can walk back to the opening layout, which matters particularly in Water Sort because pouring into the wrong empty tube frequently locks the whole position and the deadlock usually only surfaces several moves later; without unlimited undo the only remedy would be restarting. In practice you can use it to probe safely, which sharply reduces the frustration of the genre. After choosing a source tube the status line prompts you to select a destination, and an illegal pour explains that it cannot be made and asks you to choose another tube rather than silently doing nothing. Completion shows the number of moves used.

Controls and local records

Control is a two-step tap: source tube, then destination tube completes the pour. Combinations that break the rules — a destination that is neither empty nor topped with the matching colour — are refused with an explanation, so the rules enforce themselves and you need not memorise the constraints. Pouring is animated clearly so you can see exactly how many units transferred, which helps considerably in understanding the same-colour-run rule. Mouse and touch follow identical logic, the tap targets are generous, and a phone can be operated one-handed without catching a neighbouring tube. Restart is always available and undo is unlimited. A best result per difficulty is stored in the browser's local storage on your own device, with no account required and nothing uploaded; clearing browser data removes it. The language button switches between Traditional Chinese and English instantly. Once loaded, the game itself plays offline.

FAQ

Board reading and digging are explained in Water Sort Logic: Digging, Buffers and No Sandwiches.

Reviewed by the PocketJoy game-testing team · Operated by Long-Term New Media Limited · hklongtermad@gmail.com