How to play Quads: the complete rules
Quads in one paragraph: two players share a 4×4 board and 16 different pieces. Each piece is tall or short, dark or light, round or square, and solid or hollow. On your turn you place the piece your opponent chose for you, then choose a piece for them to place. Whoever completes a row, column, diagonal or 2×2 square of four pieces that share at least one trait wins. If the board fills first, it's a draw.
The 16 pieces
Every piece combines four traits, and each trait comes in two versions. Four yes-or-no traits give 2×2×2×2 = 16 combinations, and there's exactly one piece of each. No two pieces are alike.
Here's the full set:
Pieces aren't owned by either player. Both of you are building with the same shared set, which is what makes the game so tense.
How a turn works
The game starts with an empty board and all 16 pieces off to the side. The first player chooses one piece and hands it to the second player. After that, every turn has the same two steps:
- Place. Put the piece you were just handed on any empty cell. You can't refuse it or swap it.
- Hand over. Choose one of the remaining pieces and give it to your opponent. They have to place that piece on their turn.
That's the twist. You never choose the piece you place. Your opponent chooses it for you, and you choose theirs.
How to win
You win the moment you place a piece that completes a shape of four pieces sharing at least one trait. There are 19 winning shapes:
- 4 rows
- 4 columns
- 2 long diagonals
- 9 two-by-two squares (every block of four neighbouring cells)
Only one trait has to match. Four dark pieces win even if their heights, shapes and fills are all mixed:
A 2×2 square counts the same way:
A full line with no shared trait is just a full line. It doesn't win, and the game continues:
It doesn't matter who placed the first three pieces of a winning shape. The player who places the fourth piece wins, even if their opponent did most of the building.
The hand-off: the whole game in one decision
Because you choose your opponent's piece, the question on every turn is "can they win with this?" Take this position, where it's your turn to hand over a piece:
Row 2 already shares two traits, dark and short. Hand over the tall dark square solid piece and your opponent drops it on D2. That's four dark pieces, and they win. Hand over the tall light square solid piece instead. It's neither dark nor short, so it can't finish row 2, and it can't win anywhere else on this board either.
Early on, almost every piece is safe to give. As the board fills, more lines and squares get three pieces with a shared trait, and the safe pieces run out. The player who is forced to hand over a winner usually loses. Setting up that squeeze is what the strategy guide covers.
Draws and the end of the game
- The game ends the moment someone completes a winning shape.
- If all 16 pieces are placed and nobody has won, the game is a draw.
- You can't pass. You must place the piece you're given, and you must hand over a piece if any are left.
Quads vs. classic Quarto rules
If you know Quarto, the board game invented by Swiss mathematician Blaise Muller and published by Gigamic in 1991, you already know how to play Quads. The pieces, the four traits and the choose-your-opponent's-piece turn are the same. The differences are small:
| Rule | Classic Quarto | Quads |
|---|---|---|
| Board and pieces | 4×4, 16 pieces, 4 two-way traits | Same |
| Who picks the piece you place | Your opponent | Same |
| Rows, columns, diagonals win | Yes | Yes |
| 2×2 squares win | Optional advanced variant | Always on |
| Calling the win | Players announce "Quarto!" | The app spots it for you |
| Draw | Board fills with no win | Same |
Independence note: Quads is an independent game. It isn't made by, affiliated with, or endorsed by Gigamic or the makers of Quarto. We mention Quarto only because many players know the mechanic by that name.
Frequently asked questions
Do all four traits have to match to win?
No. Four pieces only need to share one trait, such as all dark or all hollow. The other three traits can be anything.
Does a 2×2 square count as a win?
In Quads, yes: any 2×2 block of four pieces sharing a trait wins. In the classic Quarto rules the square is an optional advanced variant.
What happens if the board fills up with no winner?
The game is a draw.
Can I win with a line my opponent built?
Yes. It doesn't matter who placed the other three pieces. Whoever places the fourth piece that completes a shared-trait line or square wins.
Is Quads the same as Quarto?
Quads is an independent game built on the same hand-your-opponent-the-piece mechanic as Quarto, with 16 pieces and four two-way traits. It always counts 2×2 squares as wins, and it isn't made by or affiliated with Quarto's publisher.