Serum Sort: how to solve it in few moves
Updated September 24, 2026. Figures come from the live game.
The short answer
Pour the top run of one colour onto an empty vial or onto the same colour until every vial holds one colour. A solved run scores at least 600; the rest comes from matching par moves and finishing fast. Keep one vial empty for as long as you can.
What Serum Sort decides
Every research order at the Serum Lab plays Serum Sort. It runs at your Serum Sort skill plus the level of the track you're researching, so Binding 3 is harder than Binding 1. The grade sets the research time: an S halves it.
Each colour also carries its own symbol (circle, cross, plus, triangle and so on), so you can sort by shape if colours are hard to tell apart.
The rules
- Tap a vial to lift it, then tap where it should pour.
- Only the top run of one colour moves: all of it, as much as fits.
- You can pour onto an empty vial, or onto a vial whose top colour matches. Anything else is refused on screen, and a refused pour never reaches your score.
- A vial is done when it holds one colour and is full. The puzzle is done when every vial is either done or empty.
- Undo is free to use but counts as a move.
Two rows of vials, the move counter and par up top, and Undo at the bottom.
- Moves so far, par, and the moves you have left under the budget
- A vial with room: pour onto it only when its top colour matches
- Undo is free but counts as a move
- Moves left before the run fails
How it's scored
| Part | Points | How to max it |
|---|---|---|
| Solved | 600 | Any solved run is at least a B. |
| Moves (pours plus undos) | Up to 250 | Full marks at par or better; more than par scales it down. |
| Time | Up to 150 | Full marks within 4 seconds plus 1.5 seconds per par move. It falls to 0 at four times that. |
- Par is the shortest line the generator found for that board.
- From level 8 there is a move budget: par plus some slack. Go over it and the run counts as unsolved.
- Pour faster than one pour every 250 ms on average and the run counts as unsolved, so don't rattle through taps.
How it gets harder
| Skill level | Colours | Vial size | Empty vials | Move budget | Shortest par |
|---|---|---|---|---|---|
| 1 | 4 | 5 | 2 | None | 12 |
| 5 | 6 | 5 | 2 | None | 17 |
| 8 | 7 | 5 | 2 | Par + 16 | 20 |
| 15 | 8 | 6 | 2 | Par + 12 | 29 |
| 20 | 10 | 6 | 2 | Par + 9 | 35 |
| 25 | 11 | 6 | 2 | Par + 6 | 41 |
| 30 | 12 | 6 | 2 | Par + 3 | 47 |
You always start with two empty vials. Every board is mixed deep enough that the best line takes at least the shortest par shown, vials grow to six units from level 14, and a move budget starts at level 8 and tightens as you climb.
A method that stays near par
- Before your first pour, find the colour with the most units already sitting on top of vials. Finishing it first frees the most room.
- Pour matching tops together before you touch an empty vial. Every pour onto a match costs nothing in free space.
- Treat an empty vial as your most valuable piece. Fill it only when that pour lets you finish a colour or uncover two useful tops.
- When you do use an empty vial, start it with the colour you'll complete next, so it becomes a finished vial instead of a parking spot.
- Look two pours ahead. If a pour leaves no legal move except undoing it, don't make it.
- Near the end, count what's left: with both empties free, three colours sort themselves in a few pours.
Questions players ask
What does Serum Sort gate in Voxhorde?
Research at the Serum Lab. The puzzle's level is your Serum Sort skill plus the level of the track you're researching.
Does undo cost anything in Serum Sort?
It costs no resources, but every undo counts as a move, which lowers the moves part of your score and eats into the move budget from level 8.
Is every Serum Sort puzzle solvable?
Yes. Every board is checked by a solver before it's dealt, and par is the shortest line that solver found.
Where can I practise Serum Sort?
In the Training Yard. Three paid runs a day pay out in serum and scrap, and there's a Serum Sort Daily Challenge board.