Source Lichess
Black isn't shown winning more often than losing at this level
how far wins run ahead of losses, 90% confident
At All Ratings, Blackmar-Diemer Gambit Declined: Brombacher Countergambit keeps Black's wins running −0.1% ahead of its losses at worst, 90% confident, from 39K Lichess games. The games don't show this gambit paying at this level. Win rate, draw rate and loss rate come from games played December 2023 to November 2025.
| Rating | Edge at worst | Black Win | Draw | Black Loss | Games |
|---|---|---|---|---|---|
| 0-999 | +2.4% | 53.1% | 3.2% | 43.7% | 540 |
| 1000-1199 | +4.5% | 53.4% | 3.0% | 43.6% | 941 |
| 1200-1399 | +3.1% | 51.9% | 3.4% | 44.6% | 1.6K |
| 1400-1599 | +2.5% | 51.2% | 3.3% | 45.5% | 2.6K |
| 1600-1799 | +1.5% | 50.5% | 2.9% | 46.6% | 4.5K |
| 1800-1999 | −3.2% | 47.2% | 4.2% | 48.6% | 8.4K |
| 2000-2199 | −3.4% | 46.5% | 5.2% | 48.3% | 11K |
| 2200-2499 | −2.1% | 47.2% | 5.3% | 47.5% | 8.4K |
| 2500+ | −2.6% | 47.7% | 6.0% | 46.3% | 1.7K |
1800-1999 is where the games stop proving it. Below that, Black comes out ahead; from there up, the evidence no longer shows it. Where the line sits changes with the clock, so set yours above and look again.
Black wins 48.1% of Blackmar-Diemer Gambit Declined: Brombacher Countergambit games, draws 4.5% and loses 47.4%. That rests on 39K games from Lichess.
1000-1199. There Black wins at least 4.5 more of every 100 games than it loses (90% confident), its highest Edge at worst.
Rapid. For Black, the Edge at worst — how far wins run ahead of losses, 90% confident — is −1.1% in Blitz (19K games) and +2.9% in Rapid (4.2K games).
Yes. The first rating where the games do not show Black coming out ahead is 0-999 in Bullet, 1000-1199 in Blitz and 0-999 in Rapid.
The Blackmar-Diemer Gambit Declined: Brombacher Countergambit is extremely sharp: 4.5% of its games are drawn, so 95.5% end with a winner.
Play it below 1800-1999. From there up, the games no longer show it paying. Where the line sits changes with the clock, so set yours above and look again.
As White, take the material, then develop fast, castle early, and trade pieces. Give the material back when doing so kills the attack. At 1800-1999 and above, the games no longer show Black coming out ahead with it; below that, they do.
This rests on 39K games from Lichess. Every figure carries the range it is in, 90% confident, and the table above shows how many games sit behind each rating and each clock — the fewer there are, the wider that range.