The Roman game · 100 BC
Terni Lapilli is what tic tac toe looked like two thousand years ago. Romans scratched the grid into stone everywhere they settled: pavements, forum steps, the Colosseum itself. The name means "three pebbles" in Latin. Each player had exactly three pieces to place, and once all six were on the board, the pieces started sliding instead of sitting still. That one difference changes the whole game. Read the full rules and history →
It is Latin for "three pebbles." Players used actual stones or shards of pottery as pieces. Archaeologists have found the grid scratched into surfaces all across the Roman Empire: on the steps of public buildings, in soldiers' barracks, in market squares. You can read the full history here.
The placing phase looks the same. Each player puts pieces on the board one at a time, three pieces each, trying to get three in a row. The difference comes after all six pieces are down. Instead of the game ending in a draw because the board is full, the pieces start moving. On your turn you slide one of your pieces to any adjacent empty square. The game keeps going until someone wins.
Technically yes, but it almost never happens. Because pieces keep moving, the board never fills up the way it does in regular tic tac toe. A draw can only occur if the position locks up so completely that neither player can make progress. In practice you will win or lose long before that.
Once all six pieces are on the board, each turn you choose one of your pieces and slide it to an adjacent empty square. Adjacent means any of the squares directly next to it, including diagonally. You cannot jump over other pieces. First to line up all three of your pieces wins.
Yes, and it always will be. No account, no install, no cost to slide your first pebble — just open it in any browser, on desktop or mobile.