When I was a kid, a teacher would sometimes hand out a logic puzzle. A list of clues at the top, like "the girl with the red backpack sits next to the boy who likes soccer," and a big grid of boxes below where you marked X's and O's as you worked it out.
Most of the class groaned. I loved them.
My favorite part was a specific moment. You go clue by clue, putting an X in every box that can't be right. Then you notice a row where everything is crossed out except one box. That has to be the answer. You mark it, X out the rest of that column, and suddenly that one answer unlocks the next, and the next. A minute later the whole thing falls into place.
I built a game around that feeling.
It's called Hence, a free daily logic puzzle game, and it's live now.
Hence is a modern take on those classic logic-grid puzzles, often called zebra puzzles or Einstein puzzles. The most famous one, sometimes credited to Einstein (probably wrongly), asks "who owns the zebra?" Instead of paragraphs of text, Hence uses picture clues. And there's a fresh puzzle every morning, the same for everyone.
Each day there's a 6x6 grid and a quicker 4x4. You use the clues to work out which tile goes in which column. The full rules are on the how to play page.
It looks like a simple little game. Getting it to look that simple took a lot of work. Here are the three principles I kept coming back to.
1. No guessing, ever
Every Hence puzzle has exactly one solution, and you can always reach it with pure logic. You'll never be stuck choosing between two options with no way to know which is right.
I play a lot of daily games, and I love Connections. But there's always some guessing in it. You lock in a group and never quite know if you figured it out or walked into a trap.
That's fine for a word game. For a logic puzzle, guessing ruins it. If luck can decide the outcome, winning means less and losing feels unfair.
In Hence, if you finish, you solved it. Every placement was earned. And when you're stuck, it's never a coin flip. It means there's a clue you haven't fully used yet, which is a much more fun kind of stuck.
2. Cute on purpose, clear by design
Remember the class groaning? Logic grids look like homework, and that scares people off. So the art in Hence is friendly on purpose, starting with a cast of cute little monsters that look like toys.
But cute was the easy part. Clear was the hard part.
Every item belongs to a category, and each category has its own color, so when you see an item in a clue, you know right away where to look for it.
Every item also has to be recognizable on its own, at a glance, even tiny on a phone screen. I used distinct shapes and colors so no two items could be confused. And they had to work without color too, since used clues turn gray and some players have trouble telling colors apart. So every item needed to be recognizable by its shape alone.
Those rules were strict, and they cost me some favorites. A slime monster had to go because it looked too much like the ghost. So did a whole row of cute sidekicks, because in a small clue, a spider and a monster looked the same.
That's a big reason for the toy-like style. Too little detail and items blur together. Too much and they turn into noise on a small screen. Toys are chunky, bold, and simple, with just enough detail to have personality.
Most players will never think about any of this. That's the point. They just see a clue and know what it means.
3. Look simple, especially at the start
Here's the honest problem: a full 6x6 board looks complicated. Six rows of items and a stack of clues is a lot to land on.
So almost every product decision came back to one question: how do I make this look as simple as possible, so people don't get scared off before they try?
That's why there's a short tutorial that starts with something tiny and easy, so your first experience is a win. By the time you see the real board, you already know how it works.
It's why there's a 4x4 puzzle, for anyone who finds the 6x6 too intimidating or just wants something quick.
And it's why there's no account, no sign-up, and no download. You open the site and you're playing.
Every feature idea got the same test: does this make the game feel simpler or more complicated? The first thing you see should make you think "I can do this," not "maybe later."
Come play
That's the whole idea. The same feeling I got from those school worksheets, without the worksheet. You use the picture clues to rule things out one by one, and then everything clicks.
Today's puzzle is already up, and everyone is solving the same one. It's free, there's nothing to sign up for, and it takes just a few minutes.
Play today's puzzle at hencegame.com and see how fast you can crack it.
