🧪 Tube Sort

How to play

Tube Sort is a calm, thinky pouring puzzle. Each tube holds up to four layers of colored liquid, and the colors start scrambled across your flasks. Click a tube to lift its top color block, then click a second tube to pour it in. A tube only accepts a pour if it is empty or its top layer matches the color you are pouring, and full tubes are off limits. Sort every color into its own tube to clear the level — 5 hand-built levels, each trickier than the last.

Controls

• Mouse: click a tube to select it, then click a destination tube to pour.
• Touch: tap the tubes the same way on phones and tablets.
• Keyboard: press 1–9 to pick tubes, Esc to cancel a selection, U to undo.

Tips & strategy

• Always keep one tube empty — it is your sorting room. Two empties is even better.
• Pour onto a matching top color whenever you can; burying a color under a different one creates work later.
• When you are stuck, pour a color into an empty tube to uncover what is trapped underneath.
• Undo is free and unlimited — experiment boldly and rewind the moves that do not help.
• Every shuffle is solvable, so if a level feels impossible, the answer is one clever pour away.

Scoring

Your move count is the score — clear each level in as few pours as you can. Finishing a level unlocks the next; clear all 5 levels to win the game.