Ori Tournament 2018 format

Ori Tournament 2018 Group / Bracket Format

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Group format
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All players will be ranked from 1 to N by their PB at the time signups close (February 6, 11:59 PM EST).
A number of groups will be chosen based on the following rules:
- If N is divisible by 4, then there will be (N/4) groups of 4 players each.
- If N is divisible by 5, then there will be (N/5) groups of 5 players each.
- Otherwise, we will prefer groups of 4 players each, with only 1-3 groups having 5 players each.

Assuming there are G groups, players will be assigned in order of their rank one at a time to groups 1 to G, then from G to 1, then from 1 to G, etc., until all of the players are assigned.

Groups will be played in a round-robin fashion, with each player in a group playing each other player in the group one time (regardless of the group size). At the conclusion of the group stage, players in each group will be ranked according to the following criteria:
- Wins
- Head-to-head against other players with equal wins
- Best tournament race time
- Average tournament race time
- Leaderboard PB

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Bracket format
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The bracket will be a partial double-elimination bracket, in which double elimination play continues for two rounds before the players in the lower bracket must win back into the main bracket or be eliminated. In addition, the lower half of all players (rounded up) will be seeded directly into the lower bracket.

Players are seeded into the bracket based on the group standings according to the following criteria:
- Group finish position
- Best tournament race time
- Average tournament race time
- Leaderboard PB
NOTE: if the tournament contains mixed-size groups, then 4th place and 5th place finishers will be considered equivalent for the "group finish position" criterion.

The bracket is constructed using standard bracket logic rules:
- For purposes of constructing the bracket, assume that the higher-seeded player always wins any matchup.
- At any given round, the highest-seeded remaining player should play the lowest-seeded remaining player, and the second-highest player should play the second-lowest, and so on.
- The above rule should apply for double elimination play as well, including for players falling from the main bracket to the lower bracket.

The twist is that the bracket is constructed assuming that the top half of players start in the main bracket, and the bottom half of players start in the lower bracket. We construct an example bracket with 64 players to start. As the rounds progress, you can see which seeds remain to participate, given the above assumptions:
Round 1 - main: 1-32, lower: 33-64
Lower Round 1 - lower: 17-48
Round 2 - main: 1-16, lower: 17-32
Lower Round 2 - lower: 9-24
Win-Back Round - main: 1-16
Quarterfinals - main: 1-8
Semifinals - main: 1-4
Finals: main: 1-2

In case the actual number of participants is lower than 64, we still divide the players into a top half and a bottom half (rounding up the bottom half). The top half players are seeded directly into their spots in the example bracket. The bottom half players are seeded into their spots in the example bracket, BUT if that would place a bottom half player into the main bracket, then they are treated as having lost that match by default and sent to corresponding place in the lower bracket.

For example, normally in the first round the 1 seed would meet the 32 seed. However, if there are fewer than 64 players, then the 32 seed would be in the bottom half. Thus, when seeding the bracket, the 32 seed will be placed in that slot, but then treated as though they have already lost to the 1 seed. In the lower bracket, the 33 seed would normally play against the 64 seed, with the winner facing the loser of the 1 seed versus the 32 seed, but because of the shortage of players, the 33 seed receives a bye. Thus, the 32 and 33 seeds will skip Round 1, and instead first play each other in Lower Round 1. The 1 seed will get a bye and not have to play until Round 2.

In the Win-Back Round, the remaining player from the lower bracket has an opportunity to return to the main bracket. This follows the standard double elimination format where the lower bracket player must win a best of 3 starting from an 0-1 deficit (i.e. the main bracket player only needs to win once, the lower bracket player must win twice). After that round, the double elimination portion of the bracket is concluded.

Prior to the Win-Back Round, all matches consist of a single game. The Win-Back Round, Quarterfinals, and Semifinals will be best of 3 matches, with the Win-Back Round having the aforementioned 0-1 disadvantage for the lower bracket player. The Finals of the tournament will be a best of 5 match.

(edit) In the event of having more than 64 entrants, all of the same details as above apply, but the bracket will be constructed for 128 players and the lower bracket will continue for 3 rounds.