White 89 vs Black 157
White starts from setup 89 (NNRBBKRQ), Black from setup 157 (NRNBQKBR). In the encyclopedia since 2026-10-15: neither side starts better.
|cp| ≤ 5 at 400M · 800M · 1.6B · 4B nodes, two independent engines agree
The two setups
White: setup #89 N N R B B K R Q
King on the f-file, rooks on c, g, queen on the h-file; no bishop starts in a corner; the knights start away from the centre. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 89 gives White +0.23 (Morozov Balance Index, 400M nodes).
Black: setup #157 N R N B Q K B R
King on the f-file, rooks on b, h, queen on the e-file; no bishop starts in a corner; the knights start away from the centre. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 157 gives White +0.17 (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 54.
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 0 and +20 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 89 gives White +0.23 and setup 157 gives White +0.17: 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 c4; the alternatives are slightly weaker but keep the game level.
Along the engine's main line (26 moves) the evaluation stayed within ±23 cp the whole way: the balance holds as the pieces come out, not only on move one.
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 | +20 | 1. c4 f6 2. O-O Bf7 3. h4 e5 4. e4 O-O |
| S1 | 500 000 | 16 | +3 | 1. c4 f6 2. O-O Bf7 3. h4 O-O 4. e4 e5 |
| S2 | 2 000 000 | 22 | +9 | 1. c4 f6 2. h4 e5 3. g4 c6 4. d4 Bf7 |
| S3 | 8 000 000 | 29 | +6 | 1. h4 f6 2. c4 e5 3. d4 Bf7 4. g4 c6 |
| S4 | 32 000 000 | 34 | +4 | 1. c4 f6 2. h4 Bf7 3. g4 c6 4. h5 e5 |
| S5 | 128 000 000 | 46 | 0 | 1. c4 e5 2. g4 f6 3. h4 c6 4. Nb3 Bf7 |
| S6 | 400 000 000 | 49 | 0 | 1. c4 e5 2. g4 f6 3. h4 c6 4. Nb3 Bf7 |
| S7 | 800 000 000 | 48 | 0 | 1. c4 e5 2. g4 f6 3. h4 c6 4. Nb3 Bf7 |
| S8 | 1 600 000 000 | 54 | 0 | 1. c4 e5 2. Nb3 f6 3. h4 Bf7 4. g4 c6 |
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: -6
- Lc0 0.32.1: +2
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 -10, Black +50, difference -60. 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 | 0 | 40 | 1. c4 e5 2. d4 f6 3. h4 Bf7 4. g4 c6 5. h5 Nc7 |
| 2 | -31 | 40 | 1. Nb3 b5 |
| 3 | -32 | 40 | 1. h4 b5 2. d3 f6 3. O-O Bxa2 4. c4 bxc4 5. dxc4 Bxb1 |
Main-line play-out
26 moves, 5 000 000 nodes per half-move. Largest |evaluation| 23 cp, mean 7.3 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | h4 | +13 | f6 | 0 |
| 2 | c4 | +12 | Bf7 | 0 |
| 3 | g4 | +11 | c6 | +13 |
| 4 | d3 | +17 | O-O | -3 |
| 5 | Nc2 | -10 | Nc7 | -17 |
| 6 | Ne3 | -15 | d5 | -17 |
| 7 | cxd5 | -3 | Nxd5 | -6 |
| 8 | Nxd5 | -17 | Bxd5 | -23 |
| 9 | Qh2 | -9 | Nd6 | -9 |
| 10 | Nc3 | -10 | Bf7 | -7 |
| 11 | g5 | -9 | e5 | -13 |
| 12 | Bd2 | -17 | Rc8 | -19 |
| 13 | h5 | -15 | Be6 | -11 |
| 14 | Ke1 | -9 | Qd7 | -16 |
| 15 | gxf6 | -15 | Bxf6 | -9 |
| 16 | Bg5 | -12 | Bxg5 | -16 |
| 17 | Rxg5 | 0 | Nf7 | 0 |
| 18 | Rg1 | 0 | Kh8 | 0 |
| 19 | Ne4 | 0 | Qc7 | -5 |
| 20 | Rc5 | 0 | Rce8 | 0 |
| 21 | Qg3 | 0 | Rg8 | 0 |
| 22 | a3 | 0 | Qe7 | 0 |
| 23 | b4 | 0 | Bd5 | 0 |
| 24 | Nc3 | 0 | Be6 | 0 |
| 25 | Ne4 | 0 | Ba2 | 0 |
| 26 | Nc3 | 0 | Be6 | 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 36.7 moves.
Sample game 1 (1/2-1/2)
1. h4 f6 2. g4 c6 3. c4 e5 4. Nb3 Nc7 5. d4 Bf7 6. h5 O-O 7. Bc2 Bxc4 8. Qe4 f5 9. gxf5 Qxh5 10. dxe5 Bxe2+ 11. Qxe2 Qh3+ 12. Rg2 Qh1+ 13. Rg1 Qh3+ 14. Rg2 Qh1+ 15. Rg1 Qh3+
Sample game 2 (1/2-1/2)
1. c4 f6 2. d4 e5 3. Nb3 Nab6 4. N1d2 Bf7 5. h4 O-O 6. g4 d5 7. cxd5 Bxd5 8. e4 Bf7 9. dxe5 fxe5 10. g5 Nd6 11. h5 Na4 12. g6 Be6 13. h6 hxg6 14. Nf3 Nxe4 15. Nbd2 Nxb2 16. Nxe4 Nxd1 17. Rg3 Bd5 18. hxg7 Kxg7 19. Rh3 Rh8 20. Nfg5 Rh5 21. Rxh5 gxh5 22. Rxd1 Qb5+ 23. Kg1 Bxg5 24. Qxh5 Bxe4 25. Qxg5+ Kf7 26. Qh5+ Ke6 27. Qh3+ Bf5 28. Qh6+ Kf7 29. Qh5+ Ke6 30. Qh6+ Kf7 31. Qh5+ Kf6 32. Qh6+
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 89 / 157 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): nrnbqkbr/pppppppp/8/8/8/8/PPPPPPPP/NNRBBKRQ w CGbh - 0 1
Mirror twin: White 873 vs Black 808 — a different position (castling squares are fixed), not evaluated by the search.
Current place in the live balance rating: 294.