Scorpion Solitaire: a small layout with a sharp sting
Scorpion looks a little like Spider and a little like Yukon. You build complete suits from King down to Ace inside the columns, and you can pick up any face-up card along with everything on top of it. It is a compact game: one pack, seven columns and a stock of just three cards.
It is also, on this site's rules, one of the hardest games we studied. Even a solver that could see every hidden card won only 12.9% of 3,000 deals, and it proved 67.5% impossible. That means at most about a third of Scorpion deals can be won by anyone, however skilled.
The Scorpion numbers
| What we measured | Result | Deals |
|---|---|---|
| Deals won by a solver that sees every card | 12.9% (range 11.7–14.1%) | 3,000 |
| Deals proven impossible | 67.5% (range 65.8–69.2%) | 3,000 |
| Deals left undecided | 19.6% | 3,000 |
| Deals with at least one King face down | 65.2% | 3,000 |
| Solved with 2 or more Kings face down | 14.0% | 645 |
| Solved with no King face down | 12.1% | 1,045 |
Our solver knew where every hidden card was, so these figures are a ceiling. The share of deals you can win without that knowledge is lower still, and never more than about 32.5% (12.9% solved plus 19.6% undecided).
Scorpion on solitaire-online.nz
Seven columns of seven
- Seven columns of seven cards. In the first four columns the bottom three cards are face down; everything else is face up.
- A stock of three cards, set aside at the start.
- No foundations to build on: you build full suits in the columns, and they are cleared away when complete.
Same-suit builds and group moves
- A card can go onto the next-higher card of the same suit: the 6♦ on the 7♦.
- Any face-up card can be moved, together with every card on top of it, even if those cards are not in order.
- Only a King, with whatever sits on it, may go into an empty column.
- At any time, you can deal the three stock cards: one each onto the first three columns. You get to do this once.
- When a column holds a full same-suit run from King down to Ace, it is removed. Clear all four suits to win.
Why so many deals are impossible
Two rules combine to make Scorpion tough. Building must be in suit, so each card has only one card it can go on. And only Kings can fill an empty column, so a cleared column is useful only if a King is ready to move. Add hidden cards in four columns and a tiny three-card stock, and many deals simply lock up: a card you need is underneath the card it needs to go on, and there is no way round.
Interestingly, hidden Kings made little difference in our test. Deals with two or more Kings face down were solved 14.0% of the time; deals with none face down, 12.1%. Where the Kings start seems to matter much less than how the suits are tangled.
Making a Scorpion session count
Look for locks early
Scan each suit: is any card sitting on top of the card that must go below it, with no other way to move it? If you see one, the deal may be lost from the start. With two-thirds of deals impossible, recognising that quickly saves time.
Uncover the four hidden stacks
The 12 face-down cards in the first four columns are the unknowns. Moving cards to free them tells you what you are working with.
Timing the three-card stock
You can deal the three stock cards whenever you like, but only once. Deal them when they are least likely to cover something you need, often after you have tidied the first three columns.
Use the "move anything" rule
Being able to lift any face-up card with everything above it is powerful. Use it to dig straight down to the card you need, rather than unpicking a column card by card.
Do not worry about losing
On these rules most deals cannot be won. A loss in Scorpion is usually the deal, not you. Deal again and enjoy the next one.
Scorpion on a phone
Seven columns and a small layout fit well on a phone, which makes Scorpion a good pick for a few spare minutes. Tap or drag to move groups, and zoom in if the columns get long. The game counts your moves and time for each deal.
Scorpion and Simple Simon, compared
Scorpion builds full suits in the columns, like Simple Simon. Our study shows how differently those two games treat you:
| Game | Deals won by the solver | Proven impossible |
|---|---|---|
| Scorpion (solver sees every card) | 12.9% | 67.5% |
| Simple Simon (all cards face up) | 86.5% | 5.2% |
The rules are the obvious suspects. Simple Simon lets you build in any suit and put any card into an empty column. Scorpion insists on the same suit for building and allows only Kings into empty columns. Together with its hidden cards, that turns a friendly puzzle into one where most deals lock.
How we did the research, step by step
In September 2026 the solitaire-online.nz team added Scorpion to its study, to find out how many deals on this site's rules can be won even with perfect knowledge.
- Rules from the site code. Seven columns of seven, three face-down cards in each of the first four columns, a three-card stock dealt once onto the first three columns, same-suit building, any face-up group movable, Kings only in empty columns, and full K–A suits removed automatically.
- A copy of the game. We wrote these rules into a program.
- Numbered deals. 3,000 deals from seeds 1 to 3,000.
- A solver that sees everything. It knows the twelve face-down cards and the three stock cards, and always explores the most promising position next. That makes its result a ceiling.
- A limit per deal. Up to 200,000 positions. Deals not settled by then were counted as undecided.
- A second opinion. For the deals we checked (seeds 6 and 8), a separate brute-force search confirmed the solver's verdict that they cannot be won.
- Published results. We found no published figure for Scorpion on these rules, so there is nothing to compare against.
- Error bars and limits. The 12.9% has a 95% range of 11.7% to 14.1%. Because 19.6% of deals were undecided, the true share of winnable deals is somewhere between 12.9% and 32.5%.
The technical side
Scorpion and Simple Simon share a module, spiderlike.py, written in Python 3.11 with only the standard library. The Scorpion solver is a best-first search that scores positions, always expands the best one, and keeps a record of positions already seen. A separate script, verify_scorpion_bruteforce.py, searches every possible move for a deal to double-check "impossible" verdicts. runner.py spread the work over the computer's cores using Python's multiprocessing, and the 3,000 deals took a little under 50 minutes. The ranges are Wilson score intervals. Claude, an AI assistant from Anthropic, helped us write and review the code and draft this page. The numbers come only from running the code.
By Admin, solitaire-online.nz. Study date: 19 September 2026.
Short answers before your next deal
How long does a game of Scorpion take?
We did not time Scorpion games, but the layout is small: 52 cards, seven columns and only three stock cards, so there is far less to work through than in a two-pack game.
What share of Scorpion deals is winnable?
On this site's rules, at most about a third. Our solver proved 67.5% impossible even while seeing every card.
When is the best time to use the stock?
Whenever it suits you, but only once. It usually pays to wait until the first three columns are in good shape, so the new cards do not bury something you need.
Can I move a card that has unsorted cards on top?
Yes. In Scorpion any face-up card can move with everything above it.
What is a friendlier game like this?
Spider Solitaire with one suit also builds full suits in the columns and is far more forgiving. Yukon uses the same "move any group" idea. See them all on the games page.