Lexigenesis
Don't build words. Breed them.
How to play Lexigenesis
Lexigenesis is a word game about evolution. You start with one word. Each generation your survivors breed, the environment strikes, and you choose which children live on. Survive ten generations and your lineage has made it.
The rules
- An organism is a word of three to eight letters from our word list.
- Each generation, every survivor has six offspring. Each offspring carries one mutation: a swap (one letter becomes another), an add (a letter is inserted) or a drop (a letter is removed).
- Letters tend to mutate into similar letters, so a vowel usually becomes a vowel and a consonant a consonant. About one mutation in four is lucky and lands on a real word by chance.
- An offspring that isn’t in our word list, or is shorter than three or longer than eight letters, is stillborn. It never reaches the environment.
- The environment card then strikes the living children. Depending on the card, it eats, starves or sweeps away some of them.
- You keep one or two of the survivors. Your parents don’t carry over, so the next generation comes only from your choice.
- If no child survives the card, the lineage is extinct and the run ends.
The cards
| Card | What it does |
|---|---|
| Calm | Nothing happens. Generation one is always Calm. |
| Abundance | Every survivor has nine offspring instead of six. |
| Predator | Eats every child that contains one particular letter. |
| Drought | Starves every child longer than a set length. |
| Flood | Sweeps away every child shorter than a set length. |
| Frost | Freezes children with two or more of the letters Z, X, C, V, B, N and M. |
| Radiation | Each child carries two mutations instead of one this generation. |
A worked generation
The start word is cat. Its children are cot, cast, chat, cab, caq and at. caq is stillborn because it
isn’t in our word list, and at is stillborn because it’s too small. Suppose the card is Predator O. Any child with an
o is eaten, which takes cot. Of the rest, cast, chat and cab are alive, and you keep two of them.
The forecast and breeding
The forecast shows this generation’s card and the next one, so you can plan before you choose. Your choice is confirmed with the Breed button. Evolution doesn’t take requests, so there is no undo.
Species and score
A species is any distinct word that was alive after a card in any generation, whether you kept it or not. Twins, the same child born from both parents, count once. Your score is the number of species you saw alive across the run.
The Apex
After a run, the Apex shows the best species count the game’s simulator found for that day. It is the simulator’s best lineage, not a proven maximum, so it is a target you can beat. Beat it and the game tells you that you out-evolved the simulator.
Daily and Endless
The daily run lasts ten generations and is the same for everyone. Everyone gets the same rolls for the same choices: two players who back the same word in the same generation see the same children.
Endless has no set end. It starts from its own start word, harder cards arrive as the run goes on, and it ends at extinction. Each Endless run has a short code, so you can share it. Enter a code to replay any run.
Lexigenesis strategy
Most of the skill in Lexigenesis is reading the forecast before you commit. The best lineage isn’t the one with the most children. It’s the one that can still breed after the next card.
Short common words are fertile
A short word has more single-letter neighbours that are real words, and each neighbour is a chance for a child. In our measurements about four in ten children of a three-letter word live, against about one in ten for an eight-letter word. Short common words are the safest starts. Long words are trophies, but they are easy to starve.
Read the forecast before you choose
The forecast shows this generation’s card and the next one. Before you pick survivors, ask what the next card will eat. A pair that survives the next card is worth more than a pair that only survives this one.
Hedge with two different lines
Keep survivors that differ in length and letters. If one line is caught by a Predator, the other may still carry the run. A card hits a whole group of words at once, so a spread of survivors is a hedge.
Long words are drought bait
Drought starves every child longer than its limit. If your survivors are long, one Drought can end the run. When a Drought is coming, keep one shorter word in reserve.
Twins count once, so keep your pair apart
When both parents produce the same child, it’s one species, not two. If you keep two near-identical words, they share a fate and you’ve spent a choice on one line. Pick a pair that differs, so the species count grows and the lineage survives a card that hits one of them.
Lexigenesis FAQ
Which words count?
Every organism comes from our word list, which is built from the English Speller Database (ESDB), a free, carefully curated list of English words. A child that isn’t in our word list is stillborn, so it can’t be kept.
Why was a child stillborn?
A child is stillborn when it isn’t in our word list, or when it is shorter than three letters or longer than eight. Stillborn children never reach the environment, so the card can’t touch them. The child shows why it didn’t survive.
Does everyone get the same rolls?
Yes. The mutations and the cards are set by the date, and the offspring of a word are set by its generation. Two players who back the same word in the same generation see the same children, whatever they did before. Nothing needs to be downloaded to play the daily.
What is the Apex?
The Apex is the best species count the game’s simulator found for that day’s run. It is the simulator’s best lineage, not a proven maximum, so think of it as a lower bound you can beat. Beat it and the game tells you that you out-evolved the simulator.
Can I undo?
No. Evolution doesn’t take requests. Your choice is final once you press Breed, so read the forecast first.
What is Endless?
Endless is a run with no set number of generations. It starts from its own start word, harder cards arrive as the run goes on, and it ends when the lineage goes extinct. Each Endless run has a short code, so you can share it or come back to it. Enter a code to replay any run.
Does it work offline?
Yes, once you’ve visited it at least once. After that, the daily and Endless both work with no connection.
How do I turn the music on?
Open the audio button and switch Music on. Music is off by default, and its volume is a slider in the same panel. Sound effects have their own switch, and they follow the site’s sound setting.