Tap any tile to select it, then tap any other tile to merge them. When two tiles sum to a prime number, the result locks in place and scores points.
Locked primes aren't dead — merge them with anything to build bigger primes. Combining two locked primes into a new prime earns a 2× bonus.
Scoring is exponential: prime². A 5 scores 25 pts. A 23 scores 529. Chase the big ones.
| Prime | Score | vs. five 5s |
|---|---|---|
| 5 | 25 pts | baseline |
| 11 | 121 pts | 5× better |
| 17 | 289 pts | 11× better |
| 23 | 529 pts | 21× better |
| 31 | 961 pts | 38× better |