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Bullet Rating List — IJCCRL Arena Series — Original UCI Track

IJCCRL • Bullet Rating List • Original UCI Track

Bullet Rating List — Official 1,350-Game Closure + Audited Knockout Results + Final Champion

The audited 810-game regular season remains combined with the previous official 540-game Bullet rating surface, giving an official cumulative rating corpus of 1,350 regular-season games, 675 closed mirrored units and exactly 270 games per engine with 135 White / 135 Black games each. The rating scale remains IJCCRL Ordo base 3700, and knockout games remain bracket evidence rather than rating inputs. All four Q8 matches remain closed. In Q4_M2, the raw 400-game Obsidian–Reckless package contained one D1 movetext collision in mirrored unit 12; games 23–24 were removed together to preserve the mirror contract. The homologated corpus therefore contains 398 games, 199 complete mirrored units and 199 White / 199 Black games per engine. Obsidian dev-16.15 defeated Reckless 0.10.0-dev-6abcff05 by 211.5–186.5 and advanced to the final. The final between Stockfish 18 and Obsidian dev-16.15 is now closed. The raw 600-game package contained three flag terminations; under the final audit recut, each affected game was removed together with its colour-reversed partner, excluding games 49–50, 95–96 and 115–116. The homologated final therefore contains 594 games, 297 complete mirrored units and exact 297 White / 297 Black games per engine. Stockfish 18 defeated Obsidian dev-16.15 by 369.0–225.0 and is the champion.

IJCCRL Arena Series Original UCI Track Bullet 60+2 Official AUDIT PASS Elo Base 3700 1,350 regular-season games 270 games per engine 135W / 135B each 675 mirrored units Latest phase 810 / 810 Q8 seeds closed Q8-M1 audit PASS Stockfish 18 advances Q8-M2 audit PASS Obsidian advances Q8-M3 audit PASS Reckless advances Q8-M4 audit PASS Berserk advances Q8 round closed Q4_M2 audit PASS after recut Obsidian finalist Final audit PASS after recut Stockfish 18 champion TB 1–6

Rating method

  • Previous official reference: 540 games total, 108 games per engine, Ordo base 3700.
  • New evidence: audited 810-game regular season, 162 games per engine and 81 White / 81 Black.
  • New-block performance: Ordo-style logistic fit with an explicitly estimated White advantage of approximately +198.6 Elo.
  • Update rule: (108 × previous official Elo + 162 × new-block performance) / 270.
  • Integer publication rounding preserves the final ten-engine mean at exactly 3700.
  • Knockout games remain bracket evidence and are not rating inputs.

Current audited scope

  • Latest phase: 810 / 810 accepted games.
  • Format: 10 engines, 45 pairings and 18 games per pairing.
  • Mirror integrity: 405 / 405 closed two-game units, pair ratio 0.
  • Each engine: 162 games, 81 White and 81 Black.
  • Critical incidents in accepted corpus: 0.
  • Latest regular-season winner and #1 seed: Stockfish 18.

Canonical navigation

This page remains the official Bullet Original UCI Track rating surface. Event evidence, downloadable audit packs and the rating methodology remain on their dedicated support pages.

Rating Lists hub Events Rules & Audit

Final — Official closure

Q4_M2 produced the final pairing Stockfish 18 vs Obsidian dev-16.15. The final is now forensically closed after excluding the three flag-affected mirrored units: games 49–50, 95–96 and 115–116. The official corpus contains 594 validated games, 297 complete mirrored units and 297W / 297B per engine. Stockfish 18 wins 369.0–225.0 and is the Original UCI Bullet champion.

Downloads Archive Winners
#EngineOfficial EloGamesScoreScore %W-D-LW/BStatus
1
Stockfish 18
Previous official Elo 3875 • new phase Ordo performance 3862.0 • Δ -8		3867270
108 prior + 162 current		191.0 / 27070.74%126-130-14135 / 135
Pts W/B: 125.0 / 66.0		Q#1
2
Obsidian dev-16.15
Previous official Elo 3763 • new phase Ordo performance 3756.8 • Δ -4		3759270
108 prior + 162 current		155.5 / 27057.59%90-131-49135 / 135
Pts W/B: 111.0 / 44.5		Q#2
3
Reckless 0.10.0-dev-6abcff05
Previous official Elo 3726 • new phase Ordo performance 3748.7 • Δ +14		3740270
108 prior + 162 current		148.0 / 27054.81%82-132-56135 / 135
Pts W/B: 104.5 / 43.5		Q#3
4
Berserk 14
Previous official Elo 3713 • new phase Ordo performance 3737.9 • Δ +15		3728270
108 prior + 162 current		144.0 / 27053.33%78-132-60135 / 135
Pts W/B: 102.5 / 41.5		Q#4
5
Caissa 1.24 POPCNT
Previous official Elo 3677 • new phase Ordo performance 3721.8 • Δ +27		3704270
108 prior + 162 current		135.0 / 27050.00%71-128-71135 / 135
Pts W/B: 97.5 / 37.5		Q#5
6
Clover 9.1
Previous official Elo 3710 • new phase Ordo performance 3684.3 • Δ -15		3695270
108 prior + 162 current		133.5 / 27049.44%70-127-73135 / 135
Pts W/B: 98.0 / 35.5		Q#7
7
PlentyChess 7.0.1
Previous official Elo 3689 • new phase Ordo performance 3695.0 • Δ +4		3693270
108 prior + 162 current		132.0 / 27048.89%67-130-73135 / 135
Pts W/B: 97.0 / 35.0		Q#6
8
Dragon 3.3 by Komodo Chess 64-bit
Previous official Elo 3704 • new phase Ordo performance 3668.2 • Δ -22		3682270
108 prior + 162 current		129.5 / 27047.96%56-147-67135 / 135
Pts W/B: 93.0 / 36.5		Q#8
9
RubiChess 20240817 (popcnt)
Previous official Elo 3661 • new phase Ordo performance 3633.2 • Δ -17		3644270
108 prior + 162 current		116.0 / 27042.96%43-146-81135 / 135
Pts W/B: 85.0 / 31.0		ELIMINATED
10
Integral v7.0.0
Previous official Elo 3482 • new phase Ordo performance 3492.1 • Δ +6		3488270
108 prior + 162 current		65.5 / 27024.26%17-97-156135 / 135
Pts W/B: 49.5 / 16.0		ELIMINATED

Q8 / Round of 8 — Pairings and Audited Results

Sporting seeding follows the latest 810-game regular-season classification. Q8-M1 passed after its required technical recut. Q8-M2 and Q8-M3 passed with their complete 400-game packages. Q8-M4 passed after removing games 255–256 as one indivisible mirrored unit, leaving 398 accepted games, 199 complete opening units and exact 199W / 199B allocation per engine.

Four matches closed • Q8 complete
MatchHigher seedLower seedStatus
Q8-M1
#1 Stockfish 18
Winner • 267.0 / 396 • Official Elo 3867
#8 Dragon 3.3 by Komodo Chess 64-bit
129.0 / 396 • Official Elo 3682
STOCKFISH ADVANCES
Q8-M2
#2 Obsidian dev-16.15
Winner • 244.5 / 400 • Official Elo 3759
#7 Clover 9.1
155.5 / 400 • Official Elo 3695
OBSIDIAN ADVANCES
Q8-M3
#3 Reckless 0.10.0-dev-6abcff05
Winner • 236.0 / 400 • Official Elo 3740
#6 PlentyChess 7.0.1
164.0 / 400 • Official Elo 3693
RECKLESS ADVANCES
Q8-M4
#4 Berserk 14
Winner • 213.0 / 398 • Official Elo 3728
#5 Caissa 1.24 POPCNT
185.0 / 398 • Official Elo 3704
BERSERK ADVANCES
IJCCRL • Original UCI Bullet • Q8-M1 Audit

Stockfish 18 267.0–129.0 Dragon 3.3 — Official Match PASS

The first Q8 match is validated from the corrected competitive corpus. The three proxy-fatal readyok adjudications were removed together with the valid partner game required to preserve the indivisible mirrored-unit rule. The accepted match therefore contains 396 games and 198 complete mirrored opening units.

OFFICIAL AUDIT PASS 396 / 396 accepted games 198 / 198 mirrored units 198W / 198B each Pair ratio 0 0 proxy-fatal records 0 readyok adjudications Scheduler pending null
Match winnerStockfish 18
Final score267.0–129.0
Accepted games396
Mirrored units198
Stockfish W-D-L167-200-29
Dragon W-D-L29-200-167
Colour balance198W / 198B
Critical incidents0 accepted

Correction applied before homologation

The original 400-record package contained three results awarded through proxy_fatal after an Engine w readyok timeout (12000ms). IJCCRL rules do not permit technical initialization adjudications to remain as competitive results. Original suite lines #35 and #36 were therefore removed in full: the three adjudicated records plus the valid partner game belonging to line #35. This preserved complete two-game mirror units and produced the final 396-game corpus.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Stockfish 18
Regular-season seed #1 • Official Elo 3867		267.0 / 39667.42%167-200-29198 / 198ADVANCES
2
Dragon 3.3 by Komodo Chess 64-bit
Regular-season seed #8 • Official Elo 3682		129.0 / 39632.58%29-200-167198 / 198ELIMINATED

Accepted match contract

  • Bullet 60s+2s, Original UCI Track.
  • 396 accepted games and 198 complete mirrored units.
  • 198 games with White and 198 with Black for each engine.
  • 198 retained source openings from original suite lines #1–#200, excluding #35 and #36.
  • Syzygy TB 1–6 reporting preserved in the accepted evidence.

Integrity closure

  • PGN and JSON contain the same 396 accepted games.
  • Exactly two colour-reversed games remain for every retained source opening.
  • No proxy-fatal or readyok-timeout record remains in the competitive corpus.
  • The corrected scoreboard is 267.0–129.0.
  • Stockfish 18 advances; Dragon 3.3 is eliminated from the Q8 bracket.
Rating doctrine: this Q8 result is knockout bracket evidence. Its 396 games do not modify the official 1,350-game regular-season Elo surface published above.
IJCCRL • Original UCI Bullet • Q8-M2 Audit

Obsidian dev-16.15 244.5–155.5 Clover 9.1 — Official Match PASS

The second Q8 match is homologated from the complete original competitive package. All 400 games were accepted, producing 200 closed mirrored opening units, exactly 200 White and 200 Black games per engine, and pair ratio 0. No game required exclusion or corrective recutting.

OFFICIAL AUDIT PASS 400 / 400 accepted games 200 / 200 mirrored units 200W / 200B each Pair ratio 0 0 proxy-fatal records 0 adjudications or crashes Scheduler pending null
Match winnerObsidian dev-16.15
Final score244.5–155.5
Accepted games400
Mirrored units200
Obsidian W-D-L142-205-53
Clover W-D-L53-205-142
Colour balance200W / 200B
Critical incidents0

No correction required before homologation

The complete 400-game package satisfies the IJCCRL competitive contract. There are no proxy-fatal records, readyok adjudications, engine crashes, protocol timeouts or incomplete mirror units. The single loss on time is a normal Bullet 60s+2s flag result and remains valid competitive evidence. Obsidian dev-16.15 therefore advances without any deletion from the original corpus.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Obsidian dev-16.15
Regular-season seed #2 • Official Elo 3759		244.5 / 40061.13%142-205-53200 / 200ADVANCES
2
Clover 9.1
Regular-season seed #7 • Official Elo 3695		155.5 / 40038.88%53-205-142200 / 200ELIMINATED

Accepted match contract

  • Bullet 60s+2s, Original UCI Track.
  • 400 accepted games and 200 complete mirrored units.
  • 200 games with White and 200 with Black for each engine.
  • 200 source opening lines, each used once with reversed colours.
  • Syzygy TB 1–6 reporting preserved in the accepted evidence.

Integrity closure

  • PGN and JSON contain the same 400 games in the same competitive order.
  • All 69,752 plies are legal and all final results agree with the recorded termination.
  • Termination ledger: 194 checkmates, 95 threefold repetitions, 77 insufficient-material draws, 33 fifty-move draws and one valid flag.
  • A mid-match internal counter restart introduced no duplicate game, skipped opening or mirror contamination.
  • The scheduler closes at opening index 400 with 200 White / 200 Black games per engine and pending null.
Opening-balance observation: the match produced 191 White wins, four Black wins and 205 draws. This strong source-opening colour effect does not invalidate the sporting result because all 200 positions were completed as indivisible colour-reversed mirror units.
Rating doctrine: this Q8 result is knockout bracket evidence. Its 400 games do not modify the official 1,350-game regular-season Elo surface published above.
IJCCRL • Original UCI Bullet • Q8-M3 Audit

Reckless 0.10.0-dev-6abcff05 236.0–164.0 PlentyChess 7.0.1 — Official Match PASS

The third Q8 match is homologated from the complete original competitive package. All 400 games were accepted, producing 200 closed mirrored opening units, exactly 200 White and 200 Black games per engine, and pair ratio 0. No game required exclusion or corrective recutting.

OFFICIAL AUDIT PASS 400 / 400 accepted games 200 / 200 mirrored units 200W / 200B each Pair ratio 0 0 proxy-fatal records 0 adjudications, flags or crashes Scheduler pending null
Match winnerReckless
Final score236.0–164.0
Accepted games400
Mirrored units200
Reckless W-D-L135-202-63
PlentyChess W-D-L63-202-135
Colour balance200W / 200B
Critical incidents0

No correction required before homologation

The complete 400-game package satisfies the IJCCRL competitive contract. There are no proxy-fatal records, readyok adjudications, engine crashes, protocol timeouts, losses on time or incomplete mirror units. Every recorded termination is a natural over-the-board result. Reckless 0.10.0-dev-6abcff05 therefore advances without any deletion from the original corpus.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Reckless 0.10.0-dev-6abcff05
Regular-season seed #3 • Official Elo 3740		236.0 / 40059.00%135-202-63200 / 200ADVANCES
2
PlentyChess 7.0.1
Regular-season seed #6 • Official Elo 3693		164.0 / 40041.00%63-202-135200 / 200ELIMINATED

Accepted match contract

  • Bullet 60s+2s, Original UCI Track.
  • 400 accepted games and 200 complete mirrored units.
  • 200 games with White and 200 with Black for each engine.
  • Source opening lines #1–#200, each used exactly twice with reversed colours.
  • Syzygy TB 1–6 reporting preserved throughout the accepted evidence.

Integrity closure

  • PGN and JSON contain the same 400 games with matching players, results, plies, termination data, opening metadata, duration and tablebase counters.
  • The accepted corpus contains 64,562 plies and no incomplete result.
  • Termination ledger: 198 checkmates, 143 threefold repetitions, 32 insufficient-material draws, 25 fifty-move draws and two stalemates.
  • Every source line appears in one complete colour-reversed unit; the first 16 opening plies agree inside all 200 mirror pairs.
  • The scheduler closes at opening index 400 with 200 White / 200 Black games per engine and pending null.
Mirror-unit ledger: from the Reckless perspective, 93 units ended 1.5–0.5, 86 ended 1.0–1.0 and 21 ended 0.5–1.5. No unit ended 2.0–0.0 or 0.0–2.0.
Opening-balance observation: the match produced 196 White wins, two Black wins and 202 draws. The resulting White score was 74.25%. This strong source-opening colour effect does not invalidate the sporting result because all 200 positions were completed as indivisible colour-reversed mirror units.
Rating doctrine: this Q8 result is knockout bracket evidence. Its 400 games do not modify the official 1,350-game regular-season Elo surface published above.
IJCCRL • Original UCI Bullet • Q8-M4 Audit

Berserk 14 213.0–185.0 Caissa 1.24 POPCNT — Official Match PASS After Mirrored Recut

The fourth Q8 match is homologated from a corrected 398-game competitive corpus. The original 400-game package contained one loss on time in game 255. Under the IJCCRL audit contract, game 255 and its colour-reversed partner game 256 form one indivisible opening unit and were therefore removed together. The accepted match contains 199 complete mirrored units, exactly 199 White and 199 Black games per engine, and pair ratio 0.

OFFICIAL AUDIT PASS 398 / 398 accepted games 199 / 199 mirrored units 199W / 199B each Pair ratio 0 0 flags in accepted corpus 0 technical results Scheduler pending null
Match winnerBerserk 14
Final score213.0–185.0
Accepted games398
Mirrored units199
Berserk W-D-L108-210-80
Caissa W-D-L80-210-108
Colour balance199W / 199B
Critical incidents0 accepted

Minimum correction required before homologation

The original package recorded game 255 as Berserk 14–Caissa 1.24 POPCNT 0–1 by white flag (time). Its return game, number 256, ended in a valid insufficient-material draw. Both records belong to mirrored unit 128, source opening block A48. Removing only game 255 would have broken the opening mirror, colour equality and pair ratio 0; the complete two-game unit was therefore excluded. The raw 213.5–186.5 scoreboard becomes the official audited result of 213.0–185.0.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Berserk 14
Regular-season seed #4 • Official Elo 3728		213.0 / 39853.52%108-210-80199 / 199ADVANCES
2
Caissa 1.24 POPCNT
Regular-season seed #5 • Official Elo 3704		185.0 / 39846.48%80-210-108199 / 199ELIMINATED

Accepted match contract

  • Bullet 60s+2s, Original UCI Track.
  • 398 accepted games and 199 complete mirrored units.
  • 199 games with White and 199 with Black for each engine.
  • 199 retained source openings after exclusion of mirrored unit 128.
  • Syzygy TB 1–6 reporting preserved in the accepted evidence.

Integrity closure

  • PGN and JSON agree on all 398 retained games, results and ply counts.
  • Every retained source opening appears exactly twice with reversed colours.
  • The accepted termination ledger contains 188 checkmates, 105 threefold repetitions, 78 insufficient-material draws, 21 fifty-move draws and six stalemates.
  • No flag, crash, illegal move, disconnection, readyok timeout, external adjudication or incomplete result remains.
  • The scheduler closes the original run at opening index 400 with 200 White / 200 Black records per engine and pending null; the publication corpus applies the audited two-game recut.
Rating doctrine: this Q8 result is knockout bracket evidence. Its 398 accepted games do not modify the official 1,350-game regular-season Elo surface published above.

Q4 / Semifinals — Current Bracket State

The Q4 bracket is now resolved for final qualification. Stockfish 18 is the first finalist. Q4_M2 has been forensically homologated after removal of mirrored unit 12, leaving 398 accepted games, 199 complete colour-reversed opening units and pair ratio 0. Obsidian dev-16.15 advances over Reckless 0.10.0-dev-6abcff05.

Final completed • Stockfish 18 champion
MatchHigher seedLower seedStatus
Q4_M1
#1 Stockfish 18
Official Elo 3867
#4 Berserk 14
Official Elo 3728
STOCKFISH FINALIST
Q4_M2
#2 Obsidian dev-16.15
Winner • 211.5 / 398 • Official Elo 3759
#3 Reckless 0.10.0-dev-6abcff05
186.5 / 398 • Official Elo 3740
OBSIDIAN ADVANCES
IJCCRL • Original UCI Bullet • Q4-M2 Audit

Obsidian dev-16.15 211.5–186.5 Reckless 0.10.0-dev-6abcff05 — Official Match PASS After D1 Recut

The raw Q4_M2 package contains 400 scheduler-completed games, 200 White and 200 Black records per engine, 200 mirrored units, openingIndex 400 and pending null. One D1 collision was detected because games 23 and 24, the two colour-reversed legs of mirrored unit 12, contain identical normalized movetext. D2 remains collision-free. Under the IJCCRL zero-collision audit rule, the entire two-game mirrored unit was removed. The homologated sporting corpus therefore contains 398 games.

OFFICIAL AUDIT PASS AFTER RECUT 398 / 398 accepted games 199 / 199 mirrored units 199W / 199B each Pair ratio 0 D1 0 after recut D2 0 0 open results Scheduler pending null
Match winnerObsidian dev-16.15
Final score211.5–186.5
Accepted games398
Mirrored units199
Obsidian W-D-L111-201-86
Reckless W-D-L86-201-111
Colour balance199W / 199B
Raw package issue1 D1 collision

Mandatory mirrored-unit correction

The original 400-game package fails the literal zero-collision D1 requirement because openingIndex 23 and openingIndex 24 reproduce exactly the same normalized movetext while reversing the players. Both games are draws by threefold repetition after 24 plies and belong to the same opening unit, source opening #12 / block A43. Removing only one game would break colour equality and pair ratio 0, so games 23–24 were removed together. The raw score of 212.5–187.5 becomes the official audited result of 211.5–186.5.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Obsidian dev-16.15
Regular-season seed #2 • Official Elo 3759		211.5 / 39853.14%111-201-86199 / 199ADVANCES TO FINAL
2
Reckless 0.10.0-dev-6abcff05
Regular-season seed #3 • Official Elo 3740		186.5 / 39846.86%86-201-111199 / 199ELIMINATED

Accepted match contract

  • Bullet 60s+2s, Original UCI Track.
  • 398 accepted games and 199 complete mirrored opening units.
  • 199 games with White and 199 with Black for each engine.
  • Pair ratio 0 after removal of the complete two-game unit 12.
  • Knockout evidence only; no change to the official 1,350-game Elo surface.

Integrity closure

  • PGN and results agree across the original 400-game package; the publication corpus applies the two-game audit recut.
  • Opening indexes 1–400 are continuous in the raw package; only indexes 23–24 are excluded from homologation.
  • Accepted termination ledger: 197 checkmates, 125 threefold repetitions, 43 insufficient-material draws, 27 fifty-move draws and six stalemates.
  • No crash, illegal move, disconnection, readyok timeout, external adjudication or incomplete result remains.
  • The original scheduler closes at openingIndex 400 with 200W / 200B per engine and pending null.
Colour outcome ledger: the homologated 398-game corpus contains 192 White wins, 201 draws and five Black wins. The strong opening-colour effect is neutralized competitively by the complete colour-reversed mirror structure.
Rating doctrine: Q4_M2 is knockout bracket evidence and does not modify the official 1,350-game regular-season Elo list.

FINAL — Stockfish 18 369.0–225.0 Obsidian dev-16.15

The final is officially closed after the mandatory mirrored recut. The raw 600-game package contained three losses on time. Games 49–50, 95–96 and 115–116 were excluded as three indivisible colour-reversed opening units, leaving 594 accepted games, 297 complete mirrored units, exact 297W / 297B allocation per engine and pair ratio 0.

FINAL • STOCKFISH 18 CHAMPION
PlaceEngineScoreW-D-LStatus
1
Stockfish 18
Regular-season seed #1 • Official Elo 3867
369.0 / 594
62.12%
221-296-77CHAMPION
2
Obsidian dev-16.15
Regular-season seed #2 • Official Elo 3759
225.0 / 594
37.88%
77-296-221RUNNER-UP
IJCCRL • Original UCI Bullet • Final Audit

Stockfish 18 369.0–225.0 Obsidian dev-16.15 — Official Final PASS After Mirrored Recut

The scheduler completed the full 600-game final with 300 White and 300 Black games per engine, 300 mirrored opening units, openingIndex 600 and pending null. The raw competitive ledger closed at 374.0–226.0. Three games ended by flag: opening indexes 50, 96 and 115. Under the audit treatment applied to this final, each flag-affected record was removed together with its colour-reversed partner so that no partial opening unit survived. The official homologated final therefore contains 594 games and 297 complete mirrored units.

OFFICIAL FINAL AUDIT PASS 594 / 594 accepted games 297 / 297 mirrored units 297W / 297B each Pair ratio 0 0 flags in accepted corpus 0 crashes or illegal moves Scheduler pending null
ChampionStockfish 18
Final score369.0–225.0
Accepted games594
Mirrored units297
Stockfish W-D-L221-296-77
Obsidian W-D-L77-296-221
Colour balance297W / 297B
Raw package flags3

Three mirrored units removed before homologation

The raw 600-game package contained three flag results: game 50, Obsidian dev-16.15–Stockfish 18 0–1 by white flag; game 96, Obsidian dev-16.15–Stockfish 18 0–1 by white flag; and game 115, Stockfish 18–Obsidian dev-16.15 1–0 by black flag. Their mirror partners were games 49, 95 and 116 respectively. The complete units 49–50 (A87), 95–96 (A13) and 115–116 (A14) were therefore excluded. This changes the raw 374.0–226.0 scoreboard to the official audited score of 369.0–225.0 while preserving exact colour equality and pair ratio 0.

PlaceEnginePointsScore %W-D-LWhite / BlackOutcome
1
Stockfish 18
Regular-season seed #1 • Official Elo 3867		369.0 / 59462.12%221-296-77297 / 297CHAMPION
2
Obsidian dev-16.15
Regular-season seed #2 • Official Elo 3759		225.0 / 59437.88%77-296-221297 / 297RUNNER-UP

Accepted final contract

  • Bullet 60s+2s, Original UCI Track.
  • 594 accepted games and 297 complete mirrored opening units.
  • 297 games with White and 297 with Black for each engine.
  • Pair ratio 0 after exclusion of the three complete flag-affected units.
  • Syzygy TB 1–6 reporting remains part of the final evidence package.

Integrity closure

  • The raw scheduler closed all 600 games with 300W / 300B per engine and pending null.
  • The publication corpus excludes exactly six games: 49–50, 95–96 and 115–116.
  • Accepted termination ledger: 298 checkmates, 172 threefold repetitions, 65 insufficient-material draws, 49 fifty-move draws and 10 stalemates.
  • No flag, crash, illegal move, disconnection, readyok timeout, external adjudication or incomplete result remains in the accepted corpus.
  • Stockfish 18 is the official winner of the final; no tiebreak is required.
Rating doctrine: the final is knockout bracket evidence. Its 594 accepted games do not modify the official 1,350-game regular-season Elo surface published above.
IJCCRL • Original UCI Bullet • Latest Regular Season

Audited 810-Game Phase — Official PASS and Sporting Seeds

This table remains the sporting authority for the Q8 seed order and for the #1-vs-#4 / #2-vs-#3 topology used in Q4. The Q4 bracket produced the final pairing Stockfish 18 vs Obsidian dev-16.15, and the audited final is now closed with Stockfish 18 champion by 369.0–225.0 over 594 accepted games. This sporting table remains deliberately separate from the cumulative Elo order above.

AUDIT PASS 810 / 810 games 405 / 405 mirrored units 45 pairings × 18 games 162 games per engine 81W / 81B each Pair ratio 0 0 critical incidents
Phase winnerStockfish 18
Winner score110.5 / 162
Accepted games810
Games per engine162
Mirrored units405
Games per pairing18
Colour balance81W / 81B
Q8 qualifiers8
SeedEnginePhase scoreScore %W-D-LW/BStatus
#1
Stockfish 18
Updated official Elo 3867		110.5 / 16268.21%73-75-1481 / 81QUALIFIED
#2
Obsidian dev-16.15
Updated official Elo 3759		91.5 / 16256.48%57-69-3681 / 81QUALIFIED
#3
Reckless 0.10.0-dev-6abcff05
Updated official Elo 3740		90.0 / 16255.56%54-72-3681 / 81QUALIFIED
#4
Berserk 14
Updated official Elo 3728		88.0 / 16254.32%54-68-4081 / 81QUALIFIED
#5
Caissa 1.24 POPCNT
Updated official Elo 3704		85.0 / 16252.47%53-64-4581 / 81QUALIFIED
#6
PlentyChess 7.0.1
Updated official Elo 3693		80.0 / 16249.38%42-76-4481 / 81QUALIFIED
#7
Clover 9.1
Updated official Elo 3695		78.0 / 16248.15%40-76-4681 / 81QUALIFIED
#8
Dragon 3.3 by Komodo Chess 64-bit
Updated official Elo 3682		75.0 / 16246.30%34-82-4681 / 81QUALIFIED
—
RubiChess 20240817 (popcnt)
Updated official Elo 3644		68.5 / 16242.28%26-85-5181 / 81ELIMINATED
—
Integral v7.0.0
Updated official Elo 3488		43.5 / 16226.85%16-55-9181 / 81ELIMINATED
IJCCRL • Original UCI Bullet • Official Cumulative Audit

Official Rating Closure — 1,350 Regular-Season Games

The rating table is now based on the previous official 540-game surface plus the audited 810-game phase. The cumulative contract is exactly 270 games per engine and 30 games for every one of the 45 engine pairings.

Official audit PASS 1,350 games 675 mirrored units Pair ratio 0 preserved 270 games per engine 135W / 135B each 30 games per pairing Top 8 seeded
Cumulative games1,350
Previous surface540
New audited phase810
Games per engine270
Colour balance135W / 135B
Mirrored units675
Official base3700
Rating leaderStockfish 18

Integrity checks

  • All ten engines now have exactly 270 accepted regular-season games.
  • Every engine has exactly 135 White and 135 Black games.
  • Each of the 45 engine pairings contributes exactly 30 cumulative games.
  • The cumulative corpus contains 675 closed mirrored units.
  • The final integer Elo values sum to 37,000, preserving a mean of 3700.

Historical knockout record

  • The previous completed Bullet knockout cycle remains archived as bracket evidence.
  • Previous official champion: Stockfish 18.
  • Previous final: Stockfish 18 127.5–72.5 Obsidian dev-16.15 over 200 games.
  • Those historical knockout games are not included in the 1,350-game rating corpus.
IJCCRL • Original UCI Bullet • Historical Knockout Archive

Previous Completed Knockout Cycle — Preserved Results

The preceding QF, SF and final results remain preserved below as historical bracket evidence. They do not alter the new 1,350-game regular-season rating calculation or the new Q8 seed order.

Historical cycle closed QF-M1–QF-M4 preserved SF-M1/SF-M2 preserved Final Official PASS Stockfish 18 champion
MatchWinnerScoreOpponentHistorical status
QF-M1
Stockfish 18
64.5–35.5Caissa 1.24 POPCNTCLOSED
QF-M2
Obsidian dev-16.15
64.0–36.0PlentyChess 7.0.1CLOSED
QF-M3
Reckless 0.10.0-dev-6abcff05
54.0–46.0Dragon 3.3CLOSED
QF-M4
Berserk 14
56.0–44.0Clover 9.1CLOSED
SF-M1
Stockfish 18
63.5–36.5Berserk 14CLOSED
SF-M2
Obsidian dev-16.15
56.5–43.5Reckless 0.10.0-dev-6abcff05CLOSED
FINAL
Stockfish 18
127.5–72.5Obsidian dev-16.15CHAMPION
Historical final contract: 200 games, 100 mirrored opening units, 100 White and 100 Black games per engine, pair ratio 0, scheduler pending null and no critical incident in the accepted final package.
Publication doctrine: the official Bullet Original UCI Track rating list now contains 1,350 regular-season games. Every engine has 270 games, 135 White and 135 Black. The previous official Elo surface is updated with the audited 810-game phase through game-count weighting against the new Ordo-style phase performance, while the publication mean remains exactly 3700. Q8 seeding follows only the latest regular-season sporting order.
Q8 / Q4 bracket and final: Q8-M1 is closed: Stockfish 18 defeated Dragon 3.3 by 267.0–129.0 over 396 validated games. Q8-M2 is closed: Obsidian dev-16.15 defeated Clover 9.1 by 244.5–155.5 over 400 validated games. Q8-M3 is closed: Reckless 0.10.0-dev-6abcff05 defeated PlentyChess 7.0.1 by 236.0–164.0 over 400 validated games. Q8-M4 is closed after the mandatory mirrored recut: Berserk 14 defeated Caissa 1.24 POPCNT by 213.0–185.0 over 398 validated games. Q4_M2 is officially homologated after removal of mirrored unit 12: Obsidian dev-16.15 defeated Reckless 0.10.0-dev-6abcff05 by 211.5–186.5 over 398 accepted games. The final is now closed after removal of the three complete flag-affected mirror units 49–50, 95–96 and 115–116: Stockfish 18 defeated Obsidian dev-16.15 by 369.0–225.0 over 594 accepted games and is the champion.
Build note: build 2026-08-11ORIG-BULLET-1350G-FINAL-AUDITED-CHAMPION • scope: preserve the official 1,350-game regular-season rating surface and base-3700 Elo list; preserve the audited 810-game regular-season classification, all four Q8 audit sections, Q4_M2 forensic homologation and historical knockout evidence; close the new final after the audit recut of games 49–50, 95–96 and 115–116, leaving 594 accepted games, 297 complete mirrored units, 297W / 297B per engine, pair ratio 0 and no flags in the accepted corpus; publish the official final score Stockfish 18 369.0–225.0 Obsidian dev-16.15 and Stockfish 18 as champion; final and other knockout games remain excluded from the official 1,350-game rating calculation.