Vial Sort

Goal

Sort the coloured liquids: at the end, every vial must be empty or filled with a single colour, from bottom to top.

How to play

• Tap a vial to lift it, then tap the destination vial: the top layer is poured. You can also drag one vial onto another.
• You can pour into an empty vial, or onto a layer of the same colour, as long as there is room. The whole run of the same colour on top moves at once, within the available room.
• A vial filled with a single colour is closed with a golden cork: it is finished.
• Layers marked with a “?” are hidden: their colour appears when the run covering them is poured elsewhere.
• The “Spare vial” option adds one extra empty vial, once per game.
• The “Symbols on colours” option draws a different shape on each colour, to tell them apart more easily.

Controls

• Mouse or finger: tap a vial then its destination, or drag a vial.
• Keyboard: left and right arrows to move between vials, Space or Enter to lift or pour, digits 1 to 9 to pick a vial directly, U to undo, H for a hint, P for the autopilot, F for the spare vial.

Levels and stars

From 4 colours and two empty vials (Easy) to 12 colours, 6-unit vials and many hidden layers (Devilish). Each puzzle is drawn at random and then checked by the game’s solver: it always has at least one solution. The number of pours in that solution is the target: three stars if you exceed it by less than a quarter, two stars by less than three quarters, one star otherwise. Undoing a pour removes it from the count.

Game modes

• Solo: unlimited undo, hint, restart and autopilot. The timer starts at your first move. Records (time and pours) are only registered without hints or autopilot.
• Against the AI: you and the AI get the same puzzle. It pours before your eyes in the small area, at a speed that depends on its level, and at the first levels it hesitates and takes detours. The first to finish wins; if you finish less than a second apart, the fewer pours wins.
• Two players: on the same device, each player solves the same puzzle in turn. The shortest time wins, then the fewest pours (undone pours still count).
• Online: simultaneous race, same puzzle for everyone, no hints and no undo. The fastest wins.

About the AI

The solver explores positions with a weighted A* search (identical positions are recognised whatever the order of the vials). It guarantees solvability, sets the star target, provides the hint and the autopilot, spots dead ends, and plays the opponent.