League rules

Competition formats

Each season states its format before registration. In the Swiss system, the next round pairs players with similar performance and avoids repeat opponents whenever possible. In a double round robin, every player faces everyone else twice, once in each leg; with an odd number of players, each player has one bye per leg. The number of rounds is calculated when registration closes.

How the double round robin works

When registration ends, the participant list closes and the full schedule is fixed. In the first leg, each player faces every other player once. In the second leg, exactly those matches are repeated with the order reversed. Pairings do not change according to the standings, so everyone has the same schedule and can compare their progress clearly.

With N participants, there are 2 × (N − 1) rounds if N is even and 2 × N rounds if it is odd. For example, 4 participants play 6 rounds and 5 participants play 10. Each round follows the usual two-day format: first players prepare their codes, then they solve their opponent's code.

When the number of participants is odd, one player has a bye each round. The schedule distributes the byes so that every participant has one in each leg. A bye is not a match and uses the bye points configured for the season.

One round, two days

On the first day, both opponents prepare and confirm a code. If someone misses the deadline, the server generates one automatically. On the second day, both players solve their opponent's code at the same time.

Result

The player who cracks the code in fewer attempts wins. If both use the same number, the match is drawn. If only one solves it, that player wins. Time is not a tie-breaker.

Standings and tie-breaks

The table is ordered by points and, when tied, by wins, cumulative attempt difference, lower average attempts in solved games and points earned in head-to-head matches between the players who remain tied. If all those values are equal, they share the same position.

What ‘Head-to-head’ means

‘Head-to-head’ shows the points earned in matches played between people who remain tied after the previous criteria are applied. It is used only to order that tied group: it does not award new points or change any match result.

For example, if Ana and Bea remain tied and Ana won their match, Ana has 3 head-to-head points and Bea has 0. If they drew, both have 1. If they have not yet played each other, both show 0 and share the position if there is no other difference.

Attempt difference is positive when a player solves in fewer attempts than their opponent and negative when they need more. If only one player solves, the unsolved game counts as the maximum attempts plus one. Byes, forfeits and draws add zero to this difference.

The Swiss pairing system uses the same order to match participants with similar performance in the next round, avoiding repeat opponents whenever possible. These criteria never change a win, loss or draw already recorded.

Clues

Each season states before registration whether clues are enabled. When they are allowed, the unlock point, limit and Aura cost are shown. Using clues never breaks a tie based on attempts.

Absences

A player who does not play during the solving phase loses by forfeit. If neither player plays, both receive zero points. An odd number of participants may result in a bye.

Transparency without enabling cheating

During an active round, nobody can view solutions, partial attempts or their opponent's progress. When the round closes, the codes, every attempt, their feedback, clues and the result are published.

Fair play and privacy

Only registered accounts compete. Technical signals help review incidents but do not trigger automatic penalties. By taking part, players agree that their display name, codes and solutions will be published in the season history.