White 82 vs Black 83
White starts from setup 82 (BNNRKBRQ), Black from setup 83 (BNNRKRQB). In the encyclopedia since 2026-11-01: neither side starts better.
|cp| ≤ 5 at 400M · 800M · 1.6B · 4B nodes, two independent engines agree
How to play with different setups
White sets up the pieces by position No. 82, Black by position No. 83, mirrored on their own side; the pawns stand as usual.
Moves as usual: White starts; everything else follows the Chess960 rules.
The two setups
White: setup #82 B N N R K B R Q
King on the e-file, rooks on d, g, queen on the h-file; one bishop starts in a corner; the knights start on central files. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 82 gives White +0.28 (Morozov Balance Index, 400M nodes).
Black: setup #83 B N N R K R Q B
King on the e-file, rooks on d, f, queen on the g-file; one bishop starts in a corner; the knights start on central files. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 83 gives White +0.29 (Morozov Balance Index, 400M nodes).
Why the pair is balanced
At the deepest rungs (400M, 800M, 1.6B nodes) the evaluation is exactly 0.00 each time, reaching search depth 57.
Admission rule: |cp| ≤ 5 at four budgets up to 4 billion nodes, no one-sided drift along the ladder, and confirmation by two independent engines — Berserk and Lc0 — each below its own median on symmetric positions. The same corridor is required at every deeper budget (8 G, 16 G) at which the pair has been evaluated.
The shallow rungs wandered between -11 and +18 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 82 gives White +0.28 and setup 83 gives White +0.29: with both sides on the same rank the first move is worth something. In this pair Black's own setup absorbs that edge completely.
The engine's first choice for White is g3; the alternatives are slightly weaker but keep the game level.
Along the engine's main line (29 moves) the largest swing was 36 cp (around move 1), ending at 0 cp — the position stays playable for both sides.
Engine self-play agrees: 10 games, White won 0, drawn 10, Black won 0 (White scored 50.0%).
Verification ladder
Nine independent searches of the starting position, each with a larger node budget. Evaluation in centipawns from White's point of view.
| Stage | Nodes | Depth | Eval, cp | Main line |
|---|---|---|---|---|
| S0 | 100 000 | 15 | +6 | 1. g4 Nd6 2. b3 b6 3. Bg2 Bxg2 4. Qxg2 f5 |
| S1 | 500 000 | 18 | 0 | 1. g4 Nd6 2. b3 g6 3. Nc3 f5 4. Nd3 b6 |
| S2 | 2 000 000 | 25 | -11 | 1. g4 Nd6 2. b3 g6 3. Bxh8 Qxh8 4. Bg2 h5 |
| S3 | 8 000 000 | 31 | +18 | 1. g3 g5 2. d4 Nd6 3. b3 Nc6 4. Bg2 f5 |
| S4 | 32 000 000 | 34 | 0 | 1. g3 Nc6 2. b3 Nd6 3. d4 g5 4. e3 e5 |
| S5 | 128 000 000 | 40 | +13 | 1. g3 g5 2. d4 Nc6 3. b3 Nd6 4. Bg2 f5 |
| S6 | 400 000 000 | 52 | 0 | 1. g3 g5 2. d4 Nc6 3. b3 Nd6 4. Bg2 f5 |
| S7 | 800 000 000 | 57 | 0 | 1. g3 g5 2. d4 Nc6 3. b3 Nd6 4. Bg2 f5 |
| S8 | 1 600 000 000 | 56 | 0 | 1. g3 g5 2. d4 Nc6 3. b3 Nd6 4. Bg2 f5 |
Deep verification
The search ladder reaches 1.6 billion nodes; admission needs a 4-billion rung and two further engines on top of that. Beyond even that, every pair was re-checked at budgets up to ten times larger and in thousands of self-play games. This section shows what each check returned for this pair.
| Nodes | Eval, cp |
|---|---|
| 4 000 000 000 | 0 |
| 8 000 000 000 | not checked |
| 16 000 000 000 | not checked |
This pair stays within the ±5 cp corridor up to 4 000 000 000 nodes.
Independent engines, run on the same position:
- Berserk 14: +1
- Lc0 0.32.1: +14
Independent confirmations: 3 of 3. An engine counts as confirming when its reading of the pair is closer to equality than its own reading of a typical symmetric Chess960 position (+10 for Berserk, +18 for Lc0). Where only one engine confirms, the pair is balanced according to that engine alone, and this page says so.
Own weight of each setup, measured against the classical array: White +49, Black +95, difference -46. A balanced pair needs White's setup to be weaker by about the price of the first move.
Extended self-play: 10 games, 0 White wins, 10 draws, 0 Black wins, White scored 50.0%.
Best first moves
The 3 best first moves for White, searched together at 400 000 000 nodes.
| # | Eval, cp | Depth | Main line |
|---|---|---|---|
| 1 | +6 | 42 | 1. g3 Nd6 2. d4 g5 3. b3 Nc6 4. Bg2 f5 5. h4 Nb4 |
| 2 | -17 | 41 | 1. g4 g6 2. Bg2 Nd6 3. Nc3 Nc6 4. Nd3 f5 5. gxf5 Nxf5 |
| 3 | -33 | 41 | 1. Nc3 b6 2. Nb5 Na6 3. e3 g6 4. d4 f5 5. b3 Be4 |
Main-line play-out
29 moves, 5 000 000 nodes per half-move. Largest |evaluation| 36 cp, mean 4.6 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | g3 | -13 | g5 | +36 |
| 2 | d4 | +27 | Nd6 | +8 |
| 3 | Bg2 | +22 | Nc6 | +30 |
| 4 | b3 | +33 | f5 | +13 |
| 5 | h4 | +25 | Nb4 | +16 |
| 6 | Na3 | +19 | h6 | +2 |
| 7 | c4 | 0 | O-O-O | 0 |
| 8 | Bc3 | +1 | Nc6 | -13 |
| 9 | Nb5 | -9 | Nxc4 | 0 |
| 10 | d5 | 0 | Nb2 | 0 |
| 11 | Bxb2 | 0 | Bxb2 | 0 |
| 12 | dxc6 | 0 | dxc6 | 0 |
| 13 | Nd3 | 0 | cxb5 | 0 |
| 14 | Nxb2 | 0 | Qh8 | 0 |
| 15 | Rxd8+ | 0 | Rxd8 | 0 |
| 16 | Nd1 | 0 | Rxd1+ | 0 |
| 17 | Kxd1 | 0 | Qa1+ | 0 |
| 18 | Kd2 | 0 | Qxa2+ | 0 |
| 19 | Kc3 | 0 | b4+ | 0 |
| 20 | Kxb4 | 0 | Qb2 | 0 |
| 21 | Rc1 | 0 | a5+ | 0 |
| 22 | Kc4 | 0 | b5+ | 0 |
| 23 | Kd3 | 0 | Bxg2 | 0 |
| 24 | Qxg2 | 0 | Qxc1 | 0 |
| 25 | Qa8+ | 0 | Kd7 | 0 |
| 26 | Qd5+ | 0 | Ke8 | 0 |
| 27 | Qg8+ | 0 | Kd7 | 0 |
| 28 | Qd5+ | 0 | Ke8 | 0 |
| 29 | Qg8+ | 0 | Kd7 | 0 |
Engine self-play
10 games at 500 000 nodes per move: White won 0, drawn 10, Black won 0 — White scored 50.0%. Average length 42.7 moves.
Sample game 1 (1/2-1/2)
1. g3 Nc6 2. e3 Nd6 3. Bg2 g5 4. d4 e5 5. dxe5 Nxe5 6. b3 O-O-O 7. Bxe5 Bxe5 8. Nd3 Qg7 9. Nxe5 Qxe5 10. O-O-O f5 11. h4 h6 12. Rd4 Rde8 13. Qh2 Qf6 14. Rgd1 Nb5 15. hxg5 hxg5 16. Rxd7 Rh8 17. Qg1 Qa1 18. R7d3 Kb8 19. Kd2 Qxa2 20. Nc3 Qa5 21. Ra1 Qb6 22. Nxb5 Qxb5 23. Ra4 Qe5 24. Rad4 a6 25. Qd1 Qf6 26. Bd5 Re5 27. b4 Rxd5 28. Rxd5 b5 29. Qf3 Bxd5 30. Rxd5 Rd8 31. Rxd8+ Qxd8+ 32. Ke2 Qd6 33. e4 Qxb4 34. exf5 Qc4+ 35. Ke1 g4 36. Qe3 Qxc2 37. Qf4 Qb1+ 38. Kd2 Qb2+ 39. Ke1 Qb1+ 40. Ke2 Qc2+
Sample game 2 (1/2-1/2)
1. g3 Nc6 2. e3 Nd6 3. Bg2 g5 4. d4 e5 5. dxe5 Nxe5 6. b3 O-O-O 7. Bxe5 Bxe5 8. Nd3 Qg7 9. Nxe5 Qxe5 10. O-O-O f5 11. h4 h6 12. Rd4 Rde8 13. Qh2 Qf6 14. Rgd1 Nb5 15. hxg5 hxg5 16. Rxd7 Rh8 17. Qg1 Qa1 18. R7d3 Kb8 19. Kd2 Qxa2 20. Nc3 Qa5 21. Ra1 Qb6 22. Nxb5 Qxb5 23. Ra4 Qe5 24. Rad4 a6 25. Qd1 Qf6 26. Bd5 Re5 27. b4 Rxd5 28. Rxd5 b5 29. Qf3 Bxd5 30. Rxd5 Rd8 31. Rxd8+ Qxd8+ 32. Ke2 Qd6 33. e4 Qxb4 34. exf5 Qc4+ 35. Ke1 g4 36. Qe3 Qxc2 37. Qf4 Qb1+ 38. Kd2 Qb2+ 39. Ke1 Qb1+ 40. Ke2 Qc2+
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 82 / 83 in the app's encyclopedia, then choose how to play.
- Local game — two players on one device, with a clock.
- With a mentor — a clearly labelled training bot with hints, at your level.
- Challenge a friend — an online game by link; both players get the same pair, colours swap on rematch.
Play this pair against the computer, right here Play a friend
FEN (Shredder, castling rights by rook files): bnnrkrqb/pppppppp/8/8/8/8/PPPPPPPP/BNNRKBRQ w DGdf - 0 1
Mirror twin: White 871 vs Black 867 — a different position (castling squares are fixed), not evaluated by the search.
Current place in the live balance rating: 357.