White 108 vs Black 516
White starts from setup 108 (QBNRNKBR), Black from setup 516 (RBBNQKNR). 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. 108, Black by position No. 516, 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 #108 Q B N R N K B R
King on the f-file, rooks on d, 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 108 gives White +0.14 (Morozov Balance Index, 400M nodes).
Black: setup #516 R B B N Q K N R
King on the f-file, rooks on a, h, queen on the e-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 516 gives White +0.21 (Morozov Balance Index, 400M nodes).
Why the pair is balanced
At the deepest rungs (400M, 800M, 1.6B nodes) the evaluation never left ±2 centipawns of equality, 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 -29 and +15 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 108 gives White +0.14 and setup 516 gives White +0.21: 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 d4, and 3 first moves are within 10 cp of it.
Along the engine's main line (22 moves) the evaluation stayed within ±24 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 | 13 | -29 | 1. c4 c6 2. f3 d5 3. cxd5 cxd5 4. Bf2 h5 |
| S1 | 500 000 | 20 | +5 | 1. c4 c6 2. f3 d5 3. cxd5 cxd5 4. Bf2 h5 |
| S2 | 2 000 000 | 24 | +15 | 1. f3 d5 2. d4 Nf6 3. Bf2 a5 4. O-O O-O |
| S3 | 8 000 000 | 27 | -8 | 1. d4 f5 2. h3 c6 3. Nf3 Nf7 4. c4 d6 |
| S4 | 32 000 000 | 35 | -7 | 1. d4 d6 2. e4 f5 3. exf5 Nh6 4. f6 exf6 |
| S5 | 128 000 000 | 38 | -12 | 1. d4 c6 2. c4 d5 3. cxd5 cxd5 4. f3 Nf6 |
| S6 | 400 000 000 | 47 | -2 | 1. d4 c6 2. c4 d5 3. cxd5 cxd5 4. f3 Nf6 |
| S7 | 800 000 000 | 50 | 0 | 1. d4 f5 2. h3 c6 3. Nf3 Nf6 4. c4 d6 |
| S8 | 1 600 000 000 | 57 | 0 | 1. d4 f5 2. h3 c6 3. Nf3 Nf6 4. c4 d6 |
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: -3
- Lc0 0.32.1: +4
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 +47, Black +63, difference -16. 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 | -9 | 42 | 1. d4 f5 2. h3 Nf6 3. c4 d6 4. Bh2 Nf7 5. d5 O-O |
| 2 | -11 | 41 | 1. e4 e5 2. f3 b6 3. c4 c5 4. Nc2 Ne6 5. Ne3 Ne7 |
| 3 | -18 | 41 | 1. c4 d6 2. d4 f5 3. h3 e5 4. dxe5 dxe5 5. a4 c5 |
Main-line play-out
22 moves, 5 000 000 nodes per half-move. Largest |evaluation| 24 cp, mean 8.2 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | d4 | +6 | f5 | -12 |
| 2 | h3 | -10 | c6 | -21 |
| 3 | Nf3 | -21 | Nf6 | -1 |
| 4 | c4 | -5 | d6 | -13 |
| 5 | Bh2 | -3 | Nf7 | -19 |
| 6 | d5 | -18 | b5 | -9 |
| 7 | b3 | -10 | O-O | -10 |
| 8 | O-O | -7 | a5 | -7 |
| 9 | e3 | 0 | bxc4 | +2 |
| 10 | bxc4 | +10 | Ba6 | +17 |
| 11 | Bd3 | +13 | cxd5 | +8 |
| 12 | cxd5 | +11 | Bxd3 | +6 |
| 13 | Rxd3 | 0 | Qb5 | 0 |
| 14 | a4 | 0 | Qc4 | 0 |
| 15 | Rfd1 | +22 | Ne4 | +24 |
| 16 | Nd2 | +12 | Nxd2 | +10 |
| 17 | R1xd2 | +24 | Ba7 | +4 |
| 18 | Ne2 | +4 | Rfc8 | +8 |
| 19 | Rc3 | +5 | Qe4 | +4 |
| 20 | Ng3 | +6 | Qe5 | +4 |
| 21 | Ne2 | +2 | Qe4 | 0 |
| 22 | Ng3 | 0 | Qe5 | 0 |
| 23 | Ne2 | 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 43.0 moves.
Sample game 1 (1/2-1/2)
1. f3 Nf6 2. c4 a5 3. e4 d6 4. d4 O-O 5. Bf2 b5 6. cxb5 Qxb5+ 7. Bd3 Qb7 8. O-O a4 9. Ne2 Nc6 10. Nc3 e5 11. dxe5 Nxe5 12. Qc1 c6 13. Kh1 d5 14. Bb1 dxe4 15. Nxe4 Nxe4 16. Bxe4 Be6 17. Bd4 f5 18. Bb1 Qf7 19. Qc3 Bc4 20. Rg1 Re8 21. Nd3 Bxd3 22. Bxd3 Nxd3 23. Rxd3 c5 24. Bxc5 Be5 25. Bd4 Rec8 26. Qb4 Rc4 27. Qd2 Bxd4 28. Rxd4 Rxd4 29. Qxd4 Qxa2 30. h4 h6 31. Re1 Qf7 32. Ra1 Qb7 33. Qe5 Qf7 34. Qd4 Qb7 35. Rxa4 Rxa4 36. Qxa4 Qxb2 37. Qe8+ Kh7 38. Qe6 Qc1+ 39. Kh2 Qc7+ 40. Kh3 Qf4
Sample game 2 (1/2-1/2)
1. c3 c6 2. f3 e5 3. d4 exd4 4. cxd4 d5 5. Bf2 Nf6 6. O-O Qe7 7. Ned3 O-O 8. e3 Qc7 9. Bg3 Qe7 10. Rde1 Bxg3 11. hxg3 b6 12. Nf4 Ne6 13. b3 Nxf4 14. gxf4 Ba6 15. Bd3 Bxd3 16. Nxd3 Rfc8 17. Rf2 c5 18. dxc5 bxc5 19. Rc2 c4 20. Qc1 Qe6 21. Ne5 cxb3 22. axb3 Rxc2 23. Qxc2 Rc8 24. Qb2 Qb6 25. Kf2 h6 26. g4 Qb7 27. Rd1 a5 28. Rd2 Nd7 29. Nxd7 Qxd7 30. Qd4 Qe7 31. Qxd5 Qh4+ 32. Kg2 Qe1 33. Qxa5 Qxe3 34. Rd8+ Rxd8 35. Qxd8+ Kh7 36. Qd1 Qxf4 37. Qd5 Kg8 38. Qa8+ Kh7 39. Qd5 Kg8 40. Qd8+ Kh7
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 108 / 516 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): rbbnqknr/pppppppp/8/8/8/8/PPPPPPPP/QBNRNKBR w DHah - 0 1
Mirror twin: White 860 vs Black 542 — a different position (castling squares are fixed), not evaluated by the search.
Current place in the live balance rating: 441.