Letterpress is a remarkably compelling word game for iOS, which plays something like a cross between Scrabble and Risk. When, despite not having an iPhone myself, I became addicted to playing this game on my friends' phones, I knew I had a problem.

I wanted a physical version of the game to play in person with friends and family, so I made one!

Materials needed for this project:
3 sets wooden alphabet tiles
2 bottles Rit Dye (Fuchsia and Royal Blue)
Wood veneer
1/8" plywood
1/4" plywood
Clear acrylic
Cyanoacrylate (super glue)

Tools needed:
Pot
Stove
Slotted spoon, chopsticks or other utensils (for dyeing)
Laser cutter

Step 1: Feasibility Studies

My first attempt at replicating the game play used a single set of tiles for the board, marking who owns which tiles by using colored tokens. This totally works! If you have a scrabble set and some checkers pieces, you can play Letterpress at home. Note that here we used a double stack of checkers to indicated blocked tiles.

Although this method of play worked, I found it unsatisfactory for a couple of reasons:

1. Manipulating the game pieces was awkward. Things tended to move out of grid formation, and putting markers under the tiles is a pain.

2. I found it harder to come up with words without being able to physically manipulate the tiles. It can be difficult to keep track of everything in your head, especially when you are trying to make long words.

So then I came up with a new plan: colored tiles...

Step 2: Colored Tiles

Using colored tiles improves the game play significantly. In this version, there are three identical sets of tiles in play: one neutral, one red, and one blue. Each player has a full complement of letters in their hand at any given time, and can rearrange the tiles in their hand as necessary to come up with new words.

Here, we stacked spare tiles underneath the blocked tiles, and we folded paper screens to shield each player's hand from the others.

Great! So how do you make colored tiles? There are a few options:

1. Buy them. There are a few companies that make colored scrabble tiles, such as ProTiles or SamTiles. They are a bit pricey.

2. You can buy plain wood alphabet tiles from craft suppliers, such as these, which I ended up using. Then you can either:
2.a. Color them with sharpies (this works fine, but is rather tedious); OR
2.b. Dye them, as explained in the next step.

Step 3: Dyeing Tiles

To dye the tiles, I used Rit dye, colors Fuchsia and Royal Blue. I also tried Lemon Yellow, but it hardly showed up at all on the wood.

I immersed the tiles in a solution of 2 TBSP dye to 2 cups water, kept just under boiling on the stove for 5-10 minutes.

The dye ended up being somewhat uneven, partly due to the grain, and I think partly because the tiles had a light finish which prevented them from absorbing the dye as well as they should have. However, it's perfectly sufficient to tell the difference between players.

A pair of disposable wood chopsticks was very handy during this process for stirring and manipulating tiles.

Make sure the tiles are COMPLETELY DRY before packing them away. I recommend letting them sit out on a paper towel in a sunny window for a day or two. I did not follow this advice, and one of my sets started growing mold.

Step 4: Laser Cut Boards, Trays, and Blocked Tile Markers

Just having colored tiles was a big improvement over the initial attempt, but there were still some conveniences that were lacking.

A playing board keeps the pieces aligned in grid formation, and racks allow the players to more easily rearrange their tiles while maintaining privacy. Clear acrylic tiles can be used to mark tiles which are currently blocked.

For the board:
1. Laser cut the top layer out of wood veneer.
2. Cut the bottom layer out of 1/4" wood
3. Glue the layers together with cyanoacrylate (super glue)

For the racks: Laser cut out of 1/8" plywood and assemble.

For the blocked tile markers: Laser cut out of clear acrylic.

The racks and board were modeled in Rhino. You can find the full Rhino model on github, or the dxf file attached to this step.

letterpress_kit.dxf
Download

Step 5: Game Play (rules)

Now you're ready to play Letterpress! Here's how to play:

1. Draw 25 random neutral-color tiles to populate the playing board

2. Each player selects a matching set of letters in their color, and places the letters on their rack.

3. Player 1 creates a word from some combination of the available letters and plays it on the board, exchanging the neutral colored letters for their color, and taking the neutral letters into their hand.

4. Blocked letters: If any letter of Player 1's color is completely surrounded by other letters of that color (not including diagonals), that letter is considered "blocked". This means that it cannot be captured by the other player until one of the adjacent letters is first captured, which un-blocks the letter. Mark any blocked letters with a clear acrylic tile.

5. Record the played word on a piece of paper. This can be helpful later to make sure the same word is not played more than once.

6. Player 2 plays a word. Any of the letters on the board may be used by Player 2 to form a word, including blocked letters; however, the blocked letters cannot be captured on this turn.

In order to avoid confusion when exchanging the tiles, it is helpful to follow this order of operations:
- Take the word you are about to play from the tiles in your rack, and put it on the table in front of you.
- One at a time, exchange the tiles in your word with the ones on the board, skipping blocked tiles or tiles you already control.
- Now you have a pile of letters that you just removed from the board. Put the neutral ones in your hand, and give the ones that are your opponent's color back to them, in exchange for the corresponding neutral tiles from their hand.
- Finally, once all the tiles have been exchanged, re-evaluate the blocked letters, moving the acrylic tiles as needed.
- Record the played word on a piece of paper, if desired.

Note: Each player should always have the same set of letters in their hand, in some combination of their color and neutral color.

7. Play continues until all of the neutral tiles have been captured. At this point, the player with the most tiles on the board wins.

Step 6: Addendum: Possible Variations on Game Play

Challenges and allowable words

The problem of allowable words is greatly simplified in the iOS version of the game, since the software simply doesn't let you play a word that is not allowed. I have been using the Scrabble dictionary for checking words, though any mutually agreed upon dictionary will do.

One rule in the iOS game seems to be "no repeats". But how to determine what counts a repeat? We have been using the following formula: extensions of previously played words are allowed, but subsets with no change in letter order are not allowed. For example:

If "PINNING" has been played:
- "SPINNING" is allowed (extension)
- "PIN" is not allowed (subset)
- "NIP" is allowed (different letter order)
- "PINNED" is allowed (different suffix)
- "PINING" is not allowed (subset)

Competitive types may wish to use the Scrabble rules governing challenges (if challenge is successful, player loses turn; otherwise, challenger loses turn). However, I've been playing with laxer rules -- if someone thinks a word is invalid, we simply look it up, with no loss of turns for anyone. I personally find this to be more fun, and more in keeping with the feel of iOS game play.

Number of players

We have successfully play-tested with 3 players on a 25 letter board (see photo). It worked great! I imagine you could play with an arbitrary number of players, although you would probably want a larger board. More research in this area is necessary.

Letter distribution

Most alphabet tile sets you can buy will have a letter distribution that at least approximates the natural distribution of letters in the English language. The set I used has the following distribution:

a-4, b-2, c-2, d-2, e-4, f-2, g-2, h-2, i-2, j-2, k-2, l-2, m-3, n-3, o-3, p-2, q-2, r-3, s-3, t-3, u-2, v-2, w-2, x-1, y-2, z-1

The iOS version of the game, however, has a letter distribution that is heavily weighted toward unusual letters. This has advantages and disadvantages.

One advantage of using a letter distribution that resembles the English language is that game play tends to progress faster because it is easier to come up with words. This is a big plus when you are sitting across the table from your opponent, and you don't want to wait 20 minutes for them to take their turn. However, this configuration may also be more prone to stalemate situations, where players go back and forth interminably, exchanging the same letters again and again.

We have had good luck playing with a slightly restricted set of the above letters, removing some of the more common tiles, so that there are no more than 2 of any given letter in the set.

Board geometry

With physical tiles, there's no reason to limit the game to a square board. Other layouts with a higher edge-to-area ratio or higher number of corners (such as a '+' shape geometry) could significantly alter game play by making it easier to hold on to blocked tiles. I intend to experiment with alternate board shapes in the future.

End of game considerations

In my opinion, the biggest failing of Letterpress as a game (both the iOS and physical version) is that there is a strong tendency for the game to reach a stalemate situation, which makes the end phase of the game protracted and annoying. In the majority of games I have played, the game progresses to the point where there are only a small number of tiles left (usually 3), which cannot all be used in a word together. At this point, both players realize that whoever buckles first and uses one or two of the remaining letters will open the door for their opponent to swoop in and win the game by using the final remaining letter(s). This generally leads to a long period of swapping the same letters back and forth, and often results in the players getting bored before a decisive victory can be reached.

I speculate that there may be alternate modes of game play which would ameliorate this situation. One possibility might be to maintain a running score of letters captured and consider the player who has captured the most letters after a fixed number of turns to be the winner. Some way to limit the length of games seems desirable. Board geometry and letter distribution may also have an impact on the end-of-game dynamics.

In Conclusion...

There are many open questions to investigate regarding optimization of game play! I welcome feedback or ideas from other Letterpress fans, so please leave comments!