White 13 vs Black 297
White starts from setup 13 (QNNBRKBR), Black from setup 297 (QNRBBKRN). In the encyclopedia since 2026-10-21: 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. 13, Black by position No. 297, 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 #13 Q N N B R K B R
King on the f-file, rooks on e, h, queen on the a-file; no 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 13 gives White +0.29 (Morozov Balance Index, 400M nodes).
Black: setup #297 Q N R B B K R N
King on the f-file, rooks on c, g, queen on the a-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 297 gives White +0.32 (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 55.
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 -10 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 13 gives White +0.29 and setup 297 gives White +0.32: with both sides on the same rank the first move is worth something. In this pair Black's own setup absorbs that edge completely.
White is not forced into a single path: the best first move is c4, and 2 first moves are within 10 cp of it.
Along the engine's main line (27 moves) the evaluation stayed within ±21 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 1, drawn 9, Black won 0 (White scored 55.0%).
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 | +10 | 1. c4 O-O 2. h4 c5 3. h5 f6 4. Nc3 Nc6 |
| S1 | 500 000 | 18 | +1 | 1. e4 c5 2. h4 O-O 3. h5 f6 4. c4 Nc6 |
| S2 | 2 000 000 | 24 | +18 | 1. e4 b5 2. f4 c5 3. Bf2 d6 4. d3 O-O |
| S3 | 8 000 000 | 29 | +11 | 1. e4 O-O 2. h4 c5 3. h5 f6 4. c4 Nf7 |
| S4 | 32 000 000 | 35 | 0 | 1. e4 c5 2. f4 b6 3. Nc3 O-O 4. Bf2 e6 |
| S5 | 128 000 000 | 38 | -10 | 1. e4 c5 2. f4 b5 3. Bf2 d6 4. d3 Ng6 |
| S6 | 400 000 000 | 44 | 0 | 1. e4 c5 2. h4 O-O 3. h5 b5 4. h6 gxh6 |
| S7 | 800 000 000 | 52 | 0 | 1. c4 c5 2. Nc3 f5 3. f4 b5 4. cxb5 a6 |
| S8 | 1 600 000 000 | 55 | 0 | 1. c4 c5 2. Nc3 f5 3. f3 O-O 4. Bf2 Nc6 |
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: +8
- Lc0 0.32.1: +9
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 +39, Black +33, difference +6. A balanced pair needs White's setup to be weaker by about the price of the first move.
Extended self-play: 10 games, 1 White wins, 9 draws, 0 Black wins, White scored 55.0%.
Best first moves
The 3 best first moves for White, searched together at 400 000 000 nodes.
| # | Eval, cp | Depth | Main line |
|---|---|---|---|
| 1 | +1 | 40 | 1. c4 O-O 2. Nc3 f5 3. d4 c5 4. dxc5 Rxc5 5. f3 Rc8 |
| 2 | +1 | 40 | 1. e4 c5 2. f4 b5 3. Bf2 d6 4. d3 Ng6 5. Bg3 O-O |
| 3 | -15 | 40 | 1. h4 c5 2. e4 O-O 3. h5 f6 4. Bh2 Nf7 5. a4 b6 |
Main-line play-out
27 moves, 5 000 000 nodes per half-move. Largest |evaluation| 21 cp, mean 7.1 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | e4 | +13 | c5 | -9 |
| 2 | f4 | -8 | O-O | 0 |
| 3 | Bf2 | +15 | b6 | 0 |
| 4 | Nc3 | +8 | Nc6 | +6 |
| 5 | O-O | +10 | e6 | -4 |
| 6 | f5 | -12 | f6 | -21 |
| 7 | Bg4 | -16 | exf5 | -18 |
| 8 | Bxf5 | -17 | Ne7 | -15 |
| 9 | Nd3 | -17 | Nxf5 | -21 |
| 10 | exf5 | -15 | Nf7 | -19 |
| 11 | Qd1 | -16 | Bc7 | -8 |
| 12 | Bg3 | -13 | Bxg3 | -17 |
| 13 | hxg3 | -11 | Nh6 | -13 |
| 14 | g4 | -12 | Bf7 | -15 |
| 15 | Qf3 | -13 | Qb8 | -12 |
| 16 | Re7 | 0 | Qd6 | -9 |
| 17 | Re3 | 0 | Rce8 | -7 |
| 18 | Rfe1 | 0 | c4 | 0 |
| 19 | Nf2 | 0 | Qxd2 | 0 |
| 20 | Nfe4 | 0 | Qxc2 | 0 |
| 21 | Qf4 | 0 | Qxb2 | 0 |
| 22 | Nxf6+ | 0 | gxf6 | 0 |
| 23 | Qxh6 | 0 | Qd2 | 0 |
| 24 | Qxf6 | 0 | Rxe3 | 0 |
| 25 | Qg5+ | 0 | Kh8 | 0 |
| 26 | Qf6+ | 0 | Kg8 | 0 |
| 27 | Qg5+ | 0 | Kh8 | 0 |
| 28 | Qf6+ | 0 |
Engine self-play
10 games at 500 000 nodes per move: White won 1, drawn 9, Black won 0 — White scored 55.0%. Average length 53.2 moves.
Sample game 1 (1/2-1/2)
1. e4 c5 2. f4 O-O 3. Be3 b5 4. O-O d6 5. a4 b4 6. d3 e6 7. Nd2 Ng6 8. Ncb3 Bc6 9. Nc4 Be7 10. Nca5 Be8 11. g3 Nd7 12. Bf3 Qb8 13. Nc4 Qc7 14. Nbd2 Bf6 15. a5 Bd4 16. Rf2 Nf6 17. h4 Ne7 18. Bxd4 cxd4 19. e5 dxe5 20. fxe5 Nfd5 21. Bxd5 Nxd5 22. Nb3 Ne3 23. Nxe3 dxe3 24. Rxe3 f5 25. exf6 Rxf6 26. Rxf6 gxf6 27. Re2 Bc6 28. Qe1 Bf3 29. Rxe6 Qxc2 30. Nd2 Bd5 31. Re8+ Rxe8 32. Qxe8+ Kg7 33. Qe7+ Bf7 34. Qxb4 Qxd3 35. Nf1 a6 36. Qg4+ Kf8 37. Qf4 Kg7 38. Qg4+ Kf8 39. Qf4 Kg7
Sample game 2 (1/2-1/2)
1. Nd3 b5 2. f3 a5 3. c3 d6 4. a4 Ng6 5. axb5 Bxb5 6. Bc2 c5 7. h4 h5 8. Nf2 Ne5 9. Bh2 Nbd7 10. b3 c4 11. Na3 cxb3 12. Bxb3 Ba6 13. O-O O-O 14. Qa2 Qa7 15. d4 Ng6 16. Ne4 Nxh4 17. Ng5 e6 18. Nxf7 Rxf7 19. Bxe6 Nb6 20. Rb1 d5 21. Rxb6 Bxb6 22. Qxd5 Rxc3 23. Nb5 Bxb5 24. Qxb5 Bxd4+ 25. Kh1 Re3 26. Qe8+ Kh7 27. Qxf7 Qxf7 28. Bxf7 Rxe2 29. g3 Ng2 30. Rd1 Re1+ 31. Rxe1 Nxe1 32. g4 hxg4 33. fxg4 a4 34. Bg3 Nd3 35. Bc4 Nb2 36. Ba2 Nd1 37. Kg2 Nc3 38. Bc4 a3 39. Be1 Nb5 40. Bd3+ g6 41. Bc4 Kg7 42. Bb4 Bb2 43. Kf3 Kf6 44. Kf4 Bc1+ 45. Ke4 Bb2 46. Kf4 Bc1+ 47. Ke4 Na7 48. Bc5 Nc6 49. Bd5 Nb8 50. Bd6 Nd7 51. Ba2 Kg7 52. Be6 Nf6+ 53. Kd3 Bb2
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 13 / 297 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): qnrbbkrn/pppppppp/8/8/8/8/PPPPPPPP/QNNBRKBR w EHcg - 0 1
Mirror twin: White 952 vs Black 377 — a different position (castling squares are fixed), not evaluated by the search.
Current place in the live balance rating: 108.