Spider Solitaire 2 Suits: why one extra suit changes everything
Spider 2 Suits looks like a small step up from the one-suit game. Same 104 cards, same ten columns, same five deals from the stock. The only change is that half the cards are now hearts instead of spades. Plenty of Kiwi players move up expecting a slightly harder game, and many find they have picked up a completely different one.
We measured how big the jump is. Our computer player, which sees only the face-up cards and never undoes a move, won 52.8% of one-suit games. With two suits, on the same kind of deals, it won just 5.7%. That is roughly a ninefold drop from one change to the rules.
This page explains where that drop comes from, because once you see it you can play around it. Deal a game, it is free and needs no sign-up, and read on.
The rules, and the one that matters most
The layout
- 104 cards: four full sets of spades and four of hearts.
- Ten columns, dealt six cards to each of the first four and five to the other six. Only the bottom card of each is face up.
- A 50-card stock. Each deal puts one card face up on every column, five deals in all, and there is no redeal.
How cards move
- Any card goes on a card one rank higher, of any suit. A heart 6 can sit on a spade 7.
- Only a run that is in order and all one suit can move as a block.
- Any card or same-suit run can go into an empty column.
- A complete King-to-Ace run in one suit is removed automatically. Remove all eight to win.
The game warns you if you try to deal while a column is empty.
The rule that bites
Put the first two rules side by side. You are allowed to build mixed piles, a heart 6 on a spade 7, but you cannot move them as one. A mixed pile is fine to sit in, but it locks together whatever is underneath. In the one-suit game every ordered run can move, so this problem never comes up. With two suits, every mixed build is a small commitment you cannot easily undo, and those commitments add up fast.
What our simulation found
| Measure | 1 suit | 2 suits |
|---|---|---|
| Bot win rate | 52.8% | 5.7% (95% range 5.0–6.5%) |
| Average suits cleared, out of 8 | 4.96 | 0.82 |
| Games with at least 4 suits cleared | 56.9% | 6.3% |
| Average moves in a won game | 117.5 | 154.6 |
| Column emptied before the first deal | 1.3% of games | 0.5% of games |
| Win rate after an early empty column | 98% (51 of 52) | 71% (15 of 21) |
Each column comes from 4,000 deals played by the same bot.
Most games never get going
The average two-suit game ended with fewer than one suit cleared (0.82). Only 6.3% of games reached four cleared suits. It is not that the bot got close and fell at the last hurdle. In most games it never cleared a single suit, because the columns filled up with mixed piles that could not be moved.
Winning takes longer
The two-suit wins took 154.6 moves on average, about 37 more than one-suit wins. Those extra moves are the shuffling you have to do to sort mixed piles back into single-suit runs.
An empty column still helps, but less
An early empty column is still the best sign in the game. The bot won 15 of the 21 games in which it managed one before the first deal. It is rarer than with one suit, though, and it no longer all but guarantees a win. The sample is small, so read the exact percentage loosely.
A weak bot, not a hopeless game
Be careful how you read that 5.7%. Our bot cannot see face-down cards, never takes a move back, and only looks a short way ahead. It is a lower bound, and at two suits it is a weak one. A peer-reviewed study by Blake and Gent in the Journal of Artificial Intelligence Research (2026) found that even four-suit Spider can be won in 98.5% of deals when every card is known in advance. So the two-suit game is not full of impossible deals. It is full of deals that punish short-term thinking, which is exactly what Undo and patience are for.
Playing on this site
Everything is free, with nothing to download and no account or email. It runs in any modern browser on a computer, tablet or phone.
- Unlimited Undo, the single most useful tool in two-suit Spider, plus Hint when you are stuck.
- Restart to replay the same deal and try a different plan.
- Large, clear cards with a zoom control. The two suit colours are easy to tell apart at a glance.
- Auto Play to finish a won game, and drag and drop or tap to move.
- Wins, time and moves tracked for the current game, fullscreen, table colours, and sound you can switch off.
Strategy built around the same-suit rule
1. Build in suit whenever you have the choice
If a heart 5 could go on either a heart 6 or a spade 6, choose the heart. That pile stays movable. It sounds obvious, but it is the habit that separates two-suit wins from two-suit losses.
2. Use mixed builds as a means, not an end
Sometimes the only way to uncover a card is to drop it on the other suit. Do it, but know you are borrowing. Plan how you will unpick that pile, usually by moving the top card onto a same-suit partner once one turns up.
3. Save empty columns for sorting
An empty column is the only place you can pull a mixed pile apart. Before you drop a King into one, ask whether you still need it as working space. Early in the game the answer is usually yes.
4. Uncover before you tidy
Face-down cards are what you are fighting. With two suits the game gives you more choices at each step, and it is tempting to spend them arranging nice piles. Spend them on turning cards over first.
5. Undo is part of the game
Our bot never undoes, and it wins about one game in eighteen. Players who test a line, look at what it uncovers and back out when it goes nowhere win far more. There is no score here to protect, so use Undo freely.
How we did the research, step by step
The free-solitaire.nz team ran this study in September 2026 to measure how much harder two-suit Spider is than one suit, on the rules this page uses.
- Reading the rules from this site’s own game code. Two packs, 104 cards, here in spades and hearts. Ten columns with the last card face up, a 50-card stock dealt one card to each column at a time, no redeal. Any card may go on one rank higher, but only same-suit runs move together; that rule is what makes two suits so much harder. Full King-to-Ace runs are removed automatically. We assumed you cannot deal while a column is empty.
- Rebuilding the game as a program. We rewrote Spider in Python; the one-suit and two-suit tests use the same program with only the suits changed.
- Dealing the cards. Deals 100001 to 104000, the same 4,000 seeds as our one-suit test, so the suits are the only difference.
- Choosing the player. A bot that sees only what you see and never undoes a move, looking ahead up to 250 positions before each move. It rewards same-suit links far more than mixed ones. Its result is a floor, and at two suits a weak one.
- Running it. The bot won 5.7% of 4,000 deals, against 52.8% at one suit, and cleared 0.82 suits on average.
- Checking against published research. We found no published figure for two-suit Spider. Blake & Gent, Journal of Artificial Intelligence Research, 2026 put four-suit Spider at 98.487% with every card known, which shows the deals themselves are rarely the problem.
- Working out the margin of error. A “95% range” is the band the true figure falls inside 95 times out of 100 if you ran the same test again on fresh deals. The bot’s 5.7% came with a range of 5.0–6.5%.
- What the numbers cannot tell you. Our bot has no Undo and cannot plan far ahead, and two suits punish exactly that. A careful player will do much better than 5.7%, so read it as a measure of difficulty, not as how often the game can be won.
Every deal is seeded, so the whole test can be repeated exactly.
The technical side
This page uses the same Python 3.11 module as the other Spider pages, spider.py, set to two suits. It uses only Python's standard library. A shared runner.py uses the multiprocessing module to play 19 deals side by side, and each deal is shuffled from a numbered seed starting at 100001.
- The bot looks up to 250 positions ahead on every turn, seeing only the cards a player would see. It remembers which positions it has already explored so it does not search them twice. Its score gives much more credit to a same-suit link than to a mixed-suit one, which is exactly the distinction that makes two suits hard.
- Scale. The 4,000 two-suit deals took about 14 minutes.
- The 95% range is a Wilson score interval, a standard way to put error bars on a percentage.
Because the bot's weights were tuned on seeds 1 to 30, every figure here comes from other deals, so the tuning cannot flatter the result. Claude, an AI assistant made by Anthropic, helped write and review the simulation code and draft the text. The figures are not the AI's: they come from running the code, and the team checked them against published research before publishing.
By Admin, free-solitaire.nz. Study date: 18 September 2026.
Frequently asked questions
How much harder is two-suit Spider than one-suit?
In our test, the same computer player went from winning 52.8% of one-suit games to 5.7% with two suits. People with Undo do much better than that, but most players notice a big drop at first.
Are most two-suit games impossible?
No. Research on the harder four-suit game found 98.5% of deals can be won with perfect knowledge. Two-suit losses almost always come down to the order of moves, not a hopeless deal.
Why can I build a heart on a spade but not move it?
That is the heart of the game. Mixed builds are allowed so you can reach buried cards, but only single-suit runs move as a group. It rewards building in suit whenever you can.
How long does a game take?
Winning games took our bot about 155 moves. Expect fifteen to thirty minutes, more if you use Undo to explore.
What should I play if two suits is too much?
Go back to one-suit Spider until it feels easy, or try FreeCell, where every card is face up from the start. If two suits feels comfortable, the four-suit game is the real test.
Do I need to sign up?
No. No download, no account and no email. Open the page and play.
Where can I find more games and tips?
See every game on the games page, or read strategy guides and new findings on our blog.