Yes, The Jerome Gambit Is Playable (Part 2)

[continued from previous post]

Morin, Louis (1900) - Guipi Bopala, Prince Eric (1900)
Quebec Open, Quebec, 2018
40 moves / 90 minutes, then 30 minutes

So far, we have seen a few surprises. First, White played the Jerome Gambit in a serious over-the-board tournament. Second, Black, a youngster, has been holding his own - until a bit of a surprising (second-and-a-half?), if "scientific", return of the sacrificed material.

As the game progresses, I am reminded of some points made by Dennis Monokroussos, of the chess blog The Chess Mind, in a review of Hannes Langrock's The French Defense: The Solid Rubinstein Variation (2014). The perspective can be helpful in understanding "slow" Jerome Gambits.

A couple of practical drawbacks for [those playing the variation]: if you win, it’s going to take you at least 40 moves and possibly longer. That’s not so bad if you’re playing in a civilized tournament, but here in the U.S. at least you might be playing two full-length games in one day. If you’re young and full of energy then go for it (though if you’re young and full of energy you should play sharp openings instead!), but otherwise it may be a dubious tournament strategy. It’s also not very satisfactory if you’re in a must-win situation, unless you’re a big believer in your technical abilities or your opponent’s technical shortcomings... 

To his credit, he acknowledges early on some of the criticisms readers might offer; indeed, he relates asking the very strong German grandmaster Georg Meier if he isn’t concerned about the drawish tendencies of this line. Meier’s reply was that he has been able to win many kinds of endgames with it. And that’s the key: you have to have good technique and be willing to grind out points over the long haul. Meier is young and a great technician who is able to defeat lesser lights with remarkable regularity in this opening. Our mileage may vary, but by learning the types of endings that can arise via this opening we can replicate some of his successes in our own games. 

Now: back to our game.

34.Nd4 Rb7 35.Rfe1 Rxe1 36.Rxe1 Kf7 37.Re6 Be7

Perhaps the Bishop would be better placed at f6.

38.Nc6

Louis points out that, in time trouble, he missed the winning move, 38.f5! It looks like Black must avoid taking the pawn, as 38...gxf5 39.Nxf5+ leads to the fall of Black's d-pawn. On the other hand, after 38...g5, White's Rook can go after the h-pawn, i.e. 39.Rh6 g4+ (isolating White's f-pawn) 40.Kg2. Then, the computers like 40...a4 41.Rxh6 axb3 42.axb3 when things are still pretty complicated, but White has that extra pawn.

The computers also recommend 38.g4!?, which seems counter-intuitive, opening lines for the enemy Bishop, but, after 38...hxg4+ 39.Kxg4 it becomes clear that Black's minor piece is stuck in place, and 39...Rc7 might be the best chance, pursuing activity, even at the cost of a pawn after 40.Nxb5.

Remember, though: time trouble had reared it's fearsome head. Plus: even after the text move, White is better. And: the endgame is a difficult one.

38...a4 39.b4

Continuing to cramp the enemy Bishop, although 39.bxa4 bxa4 40.g4!? might have been playable, similar to the previous note. 

39...Rc7 40.f5 gxf5 

The first time control has been reached, and White's well-posted Knight dominates Black's troubled Bishop. The extra pawn means nothing. The game is even. (It is important to remember that in difficult situations, "even" does not equal "drawn".)

41.Rh6 Bf6

The Bishop can breathe! Also, the move limits the actions of White's Rook.

42.Rh7+ Bg7 43.Rxh5 Kg6 

44.Rh4

Possibly better was 44.g4!?. taking the chance to liquidate the Kingside pawns and preparing to hang on for the draw. Of course that's easy for me to say, as I was not playing the game.

44...Bf6 45.Rf4 Rh7+ 46.Kg2 Kg5 47.Rf3 Be5 48.Re3 f4

49.gxf4+

Reasonable, but it should allow Black's King to creep closer. Tougher was 49.Re1!? keeping it all in balance.

49...Bxf4

Keeping it even. Dizzying. Tick tock!

50.Rh3

According to the computers, this is the losing move, but how would I know? It makes perfect sense to me to exchange off the major pieces, but apparently this allows Black's King greater activity. On the other hand, 50.Re8!?, which supposedly leads to the half point after mad complications, would require incredible vision.

50...Rxh3 51.Kxh3 Kf5 

The problem is that while White can trade pawn-for-pawn, Black's King gets into the action, while White's is left out.

52.Nd4+ Ke5 53.Nxb5 Bd2 54.Na7 

Black has the game in hand. Impressive.

54...Kxd5 55.b5 Kc5 56.Kg2 Bb4 57.Kf3 Kb6 58.Nc8+ Kxb5 59.Ke4 Bc5 60.Ne7 Kb4 61.Kd3 Ka3 62.Kc2 Kxa2 63.Nd5
Ka3 64.Kc3 Bf2 65.Nf4 Bg3 66.Kc2 White resigned

Hats off to young Prince Eric Guipi Bopala, for playing such a fine game!

Yes, The Jerome Gambit Is Playable (Part 1)

Is the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) playable?

I have been answering this question for over a decade - for example, see the early "But - Is this stuff Playable?? (Part I)" - and my response looks like this: in friendly games, in blitz games, in games where you are giving "Jerome Gambit odds" to a weaker player, it is playable.

Some adventurous players have not been content to leave it at that.

Years ago, I learned that English player Pete Banks ("Blackburne" online) was willing to attack with the Jerome Gambit in over-the-board games - risking his rating and the chance of teasing by his peers. See "Meet Jerome", "Jerome Gambit, Over-the-Board" and "The Pete Banks Annotated Collection" for examples.

Bill Wall, an unorthodox openings expert and Jerome Gambit afficianado in the U.S., has played some over-the-board games as well (if my records are correct). See "The Jerome Gam'",  and "Jerome Gambit: A Casual Stroll".

Of course, recently this blog has covered the escapades of Australian chess player Kevin Sheldrick (aka "Cliff Hardy"), including his effort at the 2017 Australian Open. See "Jerome Gambit: Cliff Hardy Revealed!"

It is important to not overlook the Jerome Gambit efforts of Louis Morin, of Canada, however. Anyone who has explored The Database knows that he was an early adopter of the opening, has played a truckload of games, appearing online as MrJoker (and, earlier, as a "guest"). Louis also played the Jerome Gambit at the 2015 Quebec Open. See "The Jerome Gam' again".

All of which brings us to a couple of Jerome Gambit games that Louis played at the 2018 Quebec Open.

Okay, so the Jerome Gambit is playable. But - how do you play it?


Morin, Louis (1900) - Guipi Bopala, Prince Eric (1900)
Quebec Open, Quebec, 2018
40 moves / 90 minutes, then 30 minutes

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+

Okay, this looks like the ideal time to unleash the Jerome Gambit. Black is an 11 year old - barely older than this blog. What could he know about Alonzo Wheeler Jerome's pet line?

4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf8

A wise choice. Black avoids the discomfort associated with 6...Ke6, and ducks the tactical edginess of 6...g6 7.Qxe5. He simply wants to give back a piece and take his King out of the action.

On the other hand, White has over 80 games with this position in The Database. He knows what he is doing.

7.Qxe5 d6 8.Qg3 Nf6

According to The Database, Louis is 12 - 4 - 2 against alternatives.

9.d3 

If you have played your share of Jerome Gambits, or explored games presentd on this blog, chances are that this move gave you a chuckle.

Why? Because sometimes White's strategy becomes a bit psychological - instead of racing ahead in some sort of wild attack, he signals that he will slowly and carefully work with his pawns (see "Jerome Gambit: In Pawns We Trust"). Like I wrote a couple of years ago

Steinitz said that the player with the advantage must attack, or risk losing that advantage. White prepares to face that attack, relying on solid "Jerome pawns" instead of planning an attack of his own with f2-f4.

Of course, if Black wants to protect his advantage, he has to take back the move 6...Kf8.

9...Kf7 10.O-O Rf8 11.c3 Kg8 12.d4 Bb6 13.f3 Qe7 14.Bg5 Qf7 15.Nd2 Bd7 

Black has the advantage of a piece vs two pawns, and his two Bishops are not to be discounted. Still, you can almost hear MrJoker saying "Hit me".

16.b3 a6 17.Kh1 Rae8 18.Rfe1 Be6 19.Rad1 Nh5 20.Qf2 Nf4
21.Qe3 c6 22.Bxf4 Qxf4 23.Qxf4 Rxf4

From a purely "objective" point of view, Black has to be smiling: he has escaped a tricky opening, the Queens are off the board, and there is no White attack in sight. On the other hand: what to do, what to do, what to do...

24.g3 Rff8 25.Kg2 a5 26.h3 Rf7 27.f4 g6 28.Rf1 h5 29.Nf3 Bd8 30.c4 b5

All this "doing nothing" is exhausting, even as White's pawns slowly advance like a pack of zombies. Black can hold back no longer.

31.d5 cxd5 32.cxd5 Bxh3+ 33.Kxh3 Rxe4

Argh. Black has returned his piece for a couple of pawns. He should not be too happy about his Bishop, as White's Knight will find outposts that will make it an equal game.

[to be continued]

Evans-ish Abrahams Jerome Gambit

In the previous post (see "Jerome Gambit: Move That Knight!") I shared a couple of outrageous ways (other than sacrificing it at e5) for White to move his King's Knight out of the way in the Jerome Gambit so that his Queen can enter the fray.

Of course, one "solution" is not to put the Knight there in the first place. Consider the Abrahams Jerome Gambit, 1.e4 e5 2.Bc4 Bc5 3.Bxf7+!?

I consulted The Database, and learned that it has one 1.e4 e5 2.Bc4 Bc5 3.Bxf7+ game by Bill Wall - always a good openings experimenter to check out - played on the internet in 2001. (Even that far back, he played a couple of games with 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+.)

It turns out that at the same time Bill was extending his experiments a bit, as the following game shows.

Wall, Bill - Quianna
Internet, 2001

1.e4 e5 2.Bc4 Bc5 3.b4

This move is at least as old as the MacDonnell - La Bourdonnais, London match,1834.

3...Bxb4 4.c3 Bc5 5.d4 exd4 6.Bxf7+

Here we have what might be called the "Evans-ish Abrahams Jerome Gambit", as it is not quite an Evans Gambit without Nf3/Nc6. The game follows MacDonnell - Boden, London, 1869, for 5 moves, but the first game example that I have of the move 6 Bishop sacrifice is from 2000. (Light analysis of the sacrifice is at least as old as Jaenisch's Analyse Nouvelle des ouvertures in the 1840s.)

6...Kxf7 7.Qh5+ g6 8.Qxc5

NM Eric Schiller, in notes to a game (Denker - Shayne, Rochester, New York, 1945) at Chessgames.com, said this position "looks very good for White". (It's probably about even - but for White to reach equality in 8 moves in any kind of Jerome Gambit has got to be very good, right?)

8...dxc3

The kind of pawn-grabbing that is usually punished.

Instead, Stockfish 9 suggests 8...Qe7 - as seen in Delanoy - Kamenecki, Cannes, France, 2000 (1-0, 38) - with an even game. However, Michael Goeller, a Bishop's Opening expert, gives that move a "?!" and prefers 8...Nf6 - no games in The Database - which he gives a "!", with an even game. There doesn't seem to be anything wrong with 8...Nc6 or 8...d6, either.

9.Nxc3 d6 

10.Qd5+

Psychological warfare. Bill has used a similar Queen check in the Jerome Gambit proper to question Black: Do you want to play ...Be6 and give up the b-pawn? 

10...Kf8

Black replies Not quite, and keeps his King off of the a1-h8 diagonal, where one of his Rooks lives, and where White's remaining Bishop might take up residence. Yet, 10...Kg7 might have been a better move.

11.Nf3 c6

Kicking the Queen, instead of focusing on development.

White has ample compensation for his sacrificed pawn (development, Black's unsafe King), and his opponent's next move, a nervous oversight, ends the game.

12.Qd4 c5 13.Qxh8 Black resigned

Jerome Gambit: Move That Knight!

While looking for "secrets" in the Jerome Gambit - moves or lines of play that have been discovered or recommended, but rarely, if ever, used - I occasionally run across some ideas that deserve to remain secret, because they're not really all that good.

Let me share a couple, to show you what I mean.

What do you make of this line from weenar - Quixote, blitz, FICS, 2000 (0-1, 8)?

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Ng1

Wow.

White sacrifices his Bishop at f7 to disturb Black's King, and then decides that that is enough generosity for one day. Ah, but his King's Knight is in the way of his rampaging Queen - one of the benefits, he begrudgingly admits, of 5.Nxe5+ is that it opens the d1-h5 diagonal, admittedly at the cost of another piece. 

So, the solution presents itself - move the Knight home!

A similar idea (admittedly, not after a piece sacrifice) comes to mind in such lines as 1.e4 Nf6 2.e5 Ng8!?, the Brooklyn variation of Alekhine's Defense; 1.d4 Nc6 2.d5 Nb8!?; and Stefan Bucker's 1.e4 e5 2.Nf3 f5 3.exf5 e4 4.Ng1!? against the Latvian Gambit.

Not surprisingly, the 1 win that White has out of the 5 games with the position in The Database - is a time forfeit, when Black had a winning position. One plan for Black is 5...Qh4!? 6.Qe2 Nd4 7.Nf3!? Nxe2 8.Nxh4 Nxc1, and the Queens will be off the board as White tries to find compensation for his sacrificed piece (no worry, Black's Knight at c1 will fall, but White will still only have a doubled pawn as compensation).

But, let us not laugh too loudly. What do you think of the following line?

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Ng5+

Move that Knight!

This time: not so funny. There are 515 games in The Database with 5.Ng5+. Is it surprising, or not surprising, that White scores 24%?

One "idea" behind this un-blocking Knight move is that White simply didn't notice that his piece would hang - on the average, White's rating is about 100 points below his opponent. On the other hand, there are a significant number of games where Black does not take the Knight - an indication that we are probing the depths of club and blitz play, not grandmaster praxis.

Another idea is the pair of threats - should Black capture the Knight with 5...Qxg5 - embodied in 6.d4!?, attacking both the Queen and the Bishop at c5. It is a hallucination, however, as Black has the crushing 6...Qxg2 and White is in great misery, e.g. 7.Rf1 Qxe4+  8.Be3 Nxd4 - two pieces down, behind in development, King in danger...

Why do Jerome Gambiteers play this kind of stuff? Because it's fun, I guess.

Jerome Gambit Secrets #9

As a reminder about this series:

If you play the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) you know that the best source of information on the opening is this blog. 

If you face the Jerome Gambit, however, the best source of information on defending against the opening is - this blog. 

Across the 10 years that I have shared history, games and analysis, I have done my best to give the lines that give White the greatest opportunities to snatch victory from the jaws of this defeated - er, "refuted" - opening. 

I have also not shied away from presenting the various refutations, as well. 

Sometimes players have used my suggestions. Sometimes they have not. The "Jerome Gambit Secrets" posts will re-visit suggestions that appear to remain unplayed. Occasionally, they will introduce new suggestions. 

About a decade ago I played a somewhat embarassing Jerome Gambit blitz game, perrypawnpusher - whitepandora, blitz, FICS, 2008 (1-0, 41), that started off normally, but quickly saw a quirky defense by Black.

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6 7.Qd5+ Kf6 

Certainly a King retreat is stronger plan.

I think my opponent was not taking my opening seriously, which seemed to be the case with other defenders in the next 11 games with the position, according to The Database. White scores a hefty 92%, even though the computer rates Black as clearly better.

Now, White can play the simple 8.Qxc5, which has a 6-1 record, and which has been chosen by MrJoker, Bill Wall and me (4 times).

White can also advance his d-pawn, which I will get to in a moment.

When I first posted my game on this blog, I pointed out that 8.f4!? was probably a better move - the old Jerome Gambit "d4 or f4 dilemma" again. According to Stockfish 9, Black has only an edge after 8...Qf8!? 9.Qf5+ Ke7 10.Qxc5+ Kd8 11.Qxf8+ Nxf8 12.d3.

Of course, in that case the Queens are off the board, and White's attack has disappeared. The chances to worry Black have been reduced, too.

Perhaps that is why there are still no game examples with 8.f4 in The Database. In a blitz game, especially, 8.d4 will be the choice of many Jerome Gambiteers.

8.d4 Bb4+

This is Black's best move, but it is hard not to share the alternative 8...Bxd4?? 9.Bg5#, if only because I missed the checkmate in perrypawnpusher - alvarzr, blitz, FICS, 2014 (1-0, 21).

Of course, another bad move for Black is 8...d6??, which chessfriend MrJoker did find the proper response to, 9.Bg5 checkmate.

Why was everyone having a case of nerves? I think because White's 8th move both threatens a piece and promises destruction at g5.

9.c3 c6??

I also love the automatic 9...Ba5?? 10.Bg5 checkmate, Katsampes,T - Maloney,M, St. Agnes School, St. Paul, Minnesota, 2017.

10.Qg5+ 

Missing, of course, 10.Bg5 checkmate, in a hurry to simply win Black's Queen.

Going back to move 9, Black needed to find 9...Ke7 (no game examples in The Database) Then, after 10.cxb4 Nf6 11.Qg5 Kf7 12.O-O d6 13.Nc3 Re8 would have the piece-for-two-pawns advantage that White often has to work against in the Jerome Gambit.

So - 8.f4 remains a "secret", even if it is "objectively best", and perhaps now you know why.

Also, the attractions of 8.d4 - a quick mate or win of the enemy Queen - are hardly a secret at all.

Jerome Gambit Secrets #8

?!?!?

I'll admit that sometimes when I examine "secrets" in the Jerome Gambit - recommended moves that have not, or have barely, seen the light of day, or lines that are obscure - it can seem as if things remain concealed, even after my work. Consider the following.

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Kf8 

Black messes with White's plans by bringing his King to safety, instead of taking a second piece. The Database has 212 games with this position, and White scores 54%. Stockfish 9 sees Black as less than a pawn ahead (depth of search 32 ply).

6.Nxc6 dxc6 7.O-O Bd6 

Black clearly has aggressive intentions, as he points his dark-squared Bishop toward the enemy Kingside.

I was surprised to find only 2 games in The Database with this move, one being perrypawnpusher - Lark, blitz, FICS, 2009 (1-0, 18).

By the way, Stockfish 9's suggested line of play, after a long "thought", instead of the text, is 7...g6 8.d3 Kg7. Recommending simply castling-by-hand in such a fluid position is not a lot of guidance for Black, and certainly should be encouraging for White. 

8.f4

One finesse in the Jerome Gambit that can often test the first player is which pawn to move first, the f-pawn or the d-pawn?

I am pleased to see that jfhumphrey chose the more accurate 8.d4 in his FICS blitz game again kirtz in 2012: 8.d4 Be6 9.e5 Be7 10.f4 Ke8?! 11.f5 Bd5 12.Qh5+ Bf7 13.Qg4 h5 14.Qxg7 Rh6? 15.Bxh6 Black resigned

Of course, I chose the text.

It is maddening to see that if you give Stockfish 9 a lot of time to think - 49 ply! - it suggests 8.d4 for White, and then 8...g6 (blah) for Black.

Certainly a human player is more likely to answer 8.d4 with 8...Qh5!? White should continue with 9.f4, taking advantage of the chance to form a "Jerome pawn" center. He can then counter 9...c5 with 10.c3 and then answer 10...c6 with 11.Qd3. After that, the computer likes 11...Bc7 12.Nd2 Nf6 13.e5 Nd5 14.f5 cxd4 15.cxd4

analysis diagram




White's "Jerome pawns" are on the march and are holding Black's two Bishops in check, at least for now. When White plays Nf3, it will challenge the placement of Black's Queen, after all. The position is dynamically equal.

So, of course, the computer recommends 15...Nb4 16.Qc4 Nd5 17.Qd3 Nb4, etc. with a draw by repetition of position. 

By the way, my game continued

8...g6

Okay, maybe there is something to that move.

9.d4 Bd7

Stockfish 9 prefers 9...Kg7 10.Nc3 Qh4 11.Qd3 Nh6 12.h3 Bd7 with an even game. Much of that should look familiar by now.

10.Nc3

Also playable are 10.e5 and 10.Be3, although I kind of like 10.c4!? - although it might be too much of a good thing.

The game finished up with: 10...Nh6 11.f5 Qh4 12.e5 Nxf5 13.exd6 cxd6 14.g4 Re8 15.gxf5 Bxf5 16.Qf3 Qxd4+ 17.Kh1 Kg7 18.Qf2 Black resigned

Jerome Gambit Secrets #7

Here is another Jerome Gambit line that is worth looking at, even if it is rare, if only to have a sense of how play has gone - or how it should go, if it ever appears again in a game. 

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.d4 Nc4 

Black is 2 pieces ahead, and if he wants to return some material, he has a number of choices. The text is rare method (only 3 game examples in The Database), but both players need to know a bit about what they are committed to.

7.Qh5+

This is probably White's best choice. It is a common Jerome Gambit tactic, and the resulting position is rated as equal by Stockfish 9, at an analysis level of  46 ply. We shall see, however, that in this case the computer's "opinion" is of marginal value.

The game remains complicated after the alternative 7.dxc5, which gets rid of Black's troublesome Bishop and allows White pressure along the d-file, with his advanced c-pawn ready to trouble Black's advancing d-pawn. One game by an experienced Jerome Gambiteer continued: 7...Nf6 8.e5?! (8.b3!? Ne5 9.Nc3 (9.O-O d5 10.cxd6 Qxd6 11.Nc3 -/+) 9...Re8 10.Bb2 -/+) 8...Nxe5 (8...Qe7!?) 9.Bg5 Re8 10.O-O d6 11.cxd6 cxd6 12.Nc3 Bg4 13.f3 Bh5 14.Bxf6 gxf6 15.Qd5+ Kf8 16.Qxb7 Re7 17.Qe4 (17.Qb4) 17...Bg6 (17...Nxf3+!?) 18.Qh4 Rg7 19.Nd5 Rf7?! 20.c3?! (20.f4) 20...a5 21.Rae1 a4?! 22.f4 Nc4? 23.f5 Ne5 24.fxg6 Nxg6 25.Qd4 Ra5 26.b4 (26.Re6!?) 26...Rb5 27.a3 Ne5 28.Rf4 Ng6 29.Rxf6 Rxf6 30.Nxf6 Rf5 31.Re8+ Qxe8 32.Nxe8 Kxe8 33.Qxd6 Ne7 34.b5 Rd5 35.Qb8+ Rd8 36.Qe5 Rd5 37.Qh8+ Kd7 38.b6 Rb5 39.Qd4+ Rd5 40.Qxa4+ Nc6 41.h4 Ra5 42.Qg4+ Kd6 43.a4 Ne5 44.Qb4+ Rc5 45.b7 Nc6 46.b8=Q+ Nxb8 47.Qxb8+ Kd5 48.g4 Kc4 49.Qb4+ Kd5 50.a5 Rc4 51.Qb7+ Rc6 52.a6 Kd6 53.a7 Rxc3 54.Qb8+ Kd5 55.a8=Q+ Kd4 56.Qd8+ Ke3 57.Qe7+ Kd2 58.Qg2+ Kd3 59.Qd6+ Kc4 60.Qgc6+ Kb3 61.Qb5+ Kc2 62.Qh2+ Kd1 63.Qb1+ Rc1 64.Qd6+ Ke2+ 65.Qxc1 Kf3 66.Qd3+ Kxg4 67.Qg5 checkmate, HauntedKnight - jthurman, FICS, 2014.

7... g6

Black can also try 7...Kf8, although it isn't really an improvment - and is equally complicated. One game continued 8.Qxc5+ Nd6 9.e5 b5? (9...Qe7!? is a better try 10.O-O (or 10.Qxc7 Nf5 11.Qc3 d6 12.O-O dxe5 13.dxe5 transposing) 10...Nf5 11.Qxc7 d6 12.Qc3 dxe5 13.dxe5 Bd7 14.Qf3 Qxe5 15.g4 Bb5 16.Nc3 Bxf1 17.Kxf1 Nf6 18.gxf5 Qxh2 19.Bf4 Qh5 (19...Qh4 20.Re1) 20.Qxb7 Re8 21.Qb4+ Re7 22.Kg2 Qg4+ 23.Kf1 Qh3+ 24.Kg1 Qg4+ drawn) 10.exd6 c6 11.Be3 Qa5+ 12.Nd2 Nf6 13.O-O a6 14.b4 Qd8 15.Bg5 h6 16.Bxf6 gxf6 17.Ne4 f5 18.Qxf5+ Kg7 19.Qg4+ Kh7 20.g3 a5 21.Rae1 axb4 22.Qf5+ Kg7 23.Nc5 Rxa2 24.Re7+ Kg8 25.Qf7 checkmate, HauntedKnight - Dpouchy, FICS, 2014.

While computer analysis can sometimes tease out tactical ideas, in this case Stockfish 8 & 9 frustratingly throw in the towel, suggesting 7...Kf8 8.Qf5+ Ke8 9.Qh5+ Kf8 and a draw by repetition. After all, White is two pieces down, so he should be happy with the half point.

8.Qxc5 

This capture allows White to grab the Bishop, as well, without disrupting his pawn center. The move appeared in a recent Bill Wall game, and I am a tiny bit surprised (Bill's games are full of surprises) that he didn't try the "nudge" 8.Qd5+, instead - the kind of twist that shows up in many of his games.

Looking at 8.Qd5+ Kg7, we can see that Black already has to be careful:

8...Kf8? 9.dxc5 Na5 10.Bg5 Nf6 11.Qd4 Kf7 12.e5 Nc6 13.Qc4+ d5 14.cxd6+ Be6 15.Qf4 Nxe5 16.dxc7 Qe7 17.Qxe5; or

8... Kf6? 9.Bg5+; or

8... Ke7? 9.Qxc5+ Kf7 10. Qxc4+; or

8...Ke8? 9.dxc5 Nf6 10.Qxc4. 

The game can continue in a complicated manner toward an advantage for White: 9.dxc5 Na5 10.b4 Nf6 (or 10...Nc6 11.Bb2+ Nf6, transposing) 11.Bb2 Nc6 12.b5 Re8 (or 12...Ne7 13.Qd4 Rf8 14.g4 Kg8 15.Qc4+d5 16.cxd6+ Ned5 17.Nc3 Be6 18.exd5 Bxg4 19.dxc7 Qd6 +/-) 13.bxc6 dxc6 14.Qd3 Qxd3 15.cxd3 b6 16.Nd2 Ba6 17.Rc1 Bb5 18.Nc4 Rad8 19.Ke2 Kf7 20.Bxf6 Kxf6 21.f4 Bxc4 22.Rxc4 b5 23.Rcc1 g5 +/- 

8...d5 9.Nc3 Nf6 10.e5 

Here, Black's game blew up with 10...Ne4? in Wall - Guest6959655, PlayChess.com, 2018 (1-0, 21). The defender could have maintained an even game by giving back material with 10...c6 11.exf6 Re8+ 12.Be3 Nxe3 13.fxe3 Rxe3+ 14.Kd2 Re6 15.Rae1 Rxe1 16.Rxe1 Qxf6.

So - if Black plays the almost "secret" 6...Nc4, smile, but do not celebrate yet. Go for the Queen check at h5, consider the "nudge" at d5, and prepare for complex play where you can hope for an advantage (with a draw in hand, per Stockfish).