ACWC Rules (2019 edition)

1. Organization
   1. The ACWC will be played on Lichess.
   2. The 2019 Tournament Director (TD) is ProgramFOX.
   3. In case of disputes between participants, the TD should be contacted, who will make the final call.
   4. The TD will not participate in the ACWC.
   5. Failure in complying to the rules can lead to a match forfeit or tournament disqualification, at TD discretion.
2. Player eligibility
   1. Entry requirements
      1. Your Lichess account must be created prior to March 1, 2019, 00:00 UTC.
      2. You must have played at least 100 rated Antichess games on Lichess prior to September 1, 2019, 00:00 UTC.
   2. Exceptions to these requirements can be made at TD discretion.
   3. Disqualifying elements
      1. You have an account that was marked as engine or booster after September 1, 2017.
      2. Accounts that you own that got marked before September 1, 2017, will be reviewed on a case-by-case basis but can be grounds for a disqualification.
      3. "Cheat detected" games will be reviewed on a case-by-case basis but can be grounds for a disqualification.
      4. You already entered the ACWC 2019 with another account. Your already-entered account will also be disqualified if you try to join with two accounts.
      5. No exceptions will be made for people that disqualify by rule II.C.1. If you get denied entry because of rule II.C.2 or II.C.3 at TD discretion, this cannot be disputed. (Consider an approved registration there as an exception rather than the rule, especially for II.C.2.)
      6. BOT accounts cannot play.
3. Format
   1. All games are rated and have 2+5 as time control.
   2. The tournament will consist of three stages: Qualification (Swiss), Candidates (round-robin), Final (1v1).
   3. arimakat, as 2018 winner, automatically proceeds to the Final.
   4. Ogul1, as 2018 runner-up, automatically proceeds to the Candidates.
   5. Qualification
      1. A Swiss tournament will be played between all entrants (except for arimakat and Ogul1). Each participant plays a 10-game match per round. A won match gives 1 point, a tie (5-5) gives 0.5 points, a lost match gives 0 points. Once either player reaches 5.5 in a match, the players are allowed to stop there.
      2. The number of rounds will be the base-2 logarithm of the number of participants, rounded up, plus two. So 32-63 players is 8 rounds, 64-127 players is 9 rounds, etc.
      3. Your seeding rating is equal to the average of your Antichess rating at September 1, 2019, 00:00 CEST and your highest Antichess rating between September 1, 2018, 00:00 CEST and September 1, 2019, 00:00 CEST.
      4. The three players that scored highest in the Swiss, will proceed to the Candidates.
      5. Pairings will be taken care of by the online tournament manager Challonge. The first tiebreaker is the number of wins against tied participants, the second tiebreaker employs the Median-Buchholz system. Read about the tiebreakers here. (In the unlikely event that there's still a tie after all rounds and it matters for the top 3, 10-game tiebreak matches will be played.)
   6. Candidates
      1. A round-robin tournament between the four candidates is played. Each Candidate plays a 10-game match per round. A won match gives 1 point, a tie (5-5) gives 0.5 points, a lost match gives 0 points.
      2. Players are not allowed to stop the match once either player reaches 5.5, because the exact scores may need to be used as tiebreaker.
      3. The Candidate with most points will face arimakat in the Final as Challenger. In case of a tie, the sub-scores per match get added up and used as tiebreaker.
   7. Final
      1. A 12-game match between arimakat and the Candidates winner will be played.
      2. To win the match, the leading player must be ahead by two points.
      3. If neither player achieves this, the match gets extended by two games. Repeat if still no winner.
      4. If, after 24 games, there is still no winner decided, the "must be ahead by two points" restriction gets dropped.
      5. If the score is equal (12-12), extensions proceed but with 2+0 as time control instead of 2+5, until the tie is broken (after an even number of games).
      6. If there is still no winner after 30 games total, an Armageddon game will be played, in the same way as the Atomic World Championship employs it as a tiebreaker.
         1. Black gets 3 minutes on the clock and draw odds (i.e. if draw, black wins).
         2. Both players make a time offer for White. The lowest offer plays White.
         3. In case of identical offers, the 2018 World Champion gets White.
         4. There is no increment.
4. Timeline
   1. There is one week per Qualification round (so the total number of weeks depends on the number of rounds).
   2. There is one week per round-robin round (so 3 weeks total).
   3. The Final is played as the finalists see fit.
   4. The pairings for the first Qualification round will be published before Monday 30th September 00:00 UTC.
   5. The pairings for all subsequent rounds will be published on subsequent Mondays as soon as possible (or earlier if all players finish their matches earlier).
   6. All matches of a round must be completed by Sunday 23:59:59 UTC.
5. Match negotiations

   Taken and slightly modified from the 2019 Atomic World Championship.

   1. Players may begin negotiating a playing start time as soon as their next pairing is known. When a time is agreed on, it must be shared in the Pairings forum post.
   2. To prevent (most) timezone confusion, players must communicate their times in UTC.
   3. Each player is responsible to offer at least 3 separate times for the match, by Wednesday at the latest, unless an offer has been accepted before that number is reached.
   4. The 3 offered times should be no closer than 3 hours to each other and no more than 2 on a single date.
   5. If 3 offers are not made in time the player at fault must accept a time chosen by the opponent.
   6. If both players fail to make 3 offers by the deadline then a TD will assign a time.
   7. A player should respond to an offer by accepting or making a different offer, preferably within 24 hours.
   8. If both players make 3 offers but no agreement is made before the weekend then a TD will determine if fault lies with a particular player.
   9. If a player is at fault then their opponent will decide the match time, if no player is at fault the TD will assign a match time.
6. Match rules (applying at all stages)
   1. Each player has the right to call a break once during the match, between two games. The break lasts at most 10 minutes.
   2. If no break is called, a rematch must be offered and accepted immediately. Repeated failure in doing so leads to a forfeit.
   3. In the Final: the same break rules apply, but because the Final can take much longer than a standard match, the finalists are allowed to split their match over several days.
   4. If a player is offline at the time of the match, they have a 10 minute grace period to come online and start the game. The appearing player has to message the TD that their opponent did not show up and again 10 minutes afterwards if the opponent still didn't show up. The appearing player has the choice to reschedule or claim a win. If the appearing player does not claim a win and rescheduling fails, the match will be forfeited in favor of the appearing player.
   5. If a player leaves the match while it's still ongoing, they get 10 minutes to come back and this counts as their break. If they don't come back in time, their opponent gets the option to claim a win (similar to rule rule VI.D).
   6. If a player gets forfeited in two different matches, they get disqualified from the ACWC.
   7. After a match, either player must post the results in the Pairings forum post.
7. Reporting cheats
   1. Accusations of cheating must be made privately to the TD. Any accusation in public will result in a disqualification of the accuser, regardless of whether the accusation was correct or not.
   2. If an accused player is found guilty, they will be disqualified from the tournament.
   3. If a player gets marked as engine/booster on Lichess during the ACWC but for non-ACWC games, they also get disqualified from the ACWC.
8. Disqualification and withdrawals
   1. Qualifications
      1. If a player withdraws or gets disqualified from the Qualification, they will not be included in later pairings. If they still have an uncompleted pairing, their opponent wins this game.
      2. If the disqualification happens on grounds of an engine mark (not booster mark), all of their finished games in the Qualification will be adjudicated in favor of their opponents.
   2. Candidates: if a player withdraws or gets disqualified from the Candidates, all of their games will be disregarded.
   3. Finals
      1. If arimakat withdraws or gets disqualified, the Challenger plays the Candidates runner-up in the Final.
      2. If the Challenger withdraws or gets disqualified, the Candidates runner-up becomes the new Challenger.