What is Black’s sharpest response to 1. d4?

Benko Gambit 100%.

And I like the Englund there are several playable lines.

But I don't do this stuff I like slow games... I go Nimzo, keep it normal and boring

I myself play the Dutch and assure you it is not the sharpest of all defenses to d4. More in the middle somewhere.

If someone pointed a gun to my head and asked me what the sharpest line that starts 1.d4 is, I'd probably say it would be between the Anti-Moscow Variation and the Botvinnik Variation of the Semi-Slav. Both start 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5.

The Anti-Moscow is now 5...h6 6.Bh4.

The Botvinnik is now 5...dxc4.

I myself played the latter when I was in my mid-20s. Too old for that garbage now!

I'd have to agree with ThrillerFan here, it's likely a Semi-Slav, be it the Meran, Anti-Moscow, or Botvinnik, but I could also see it being one of the more complex QGD variations or the Mar del Plata KID.

Modern Benoni. Not the Benko Gambit .... that's not really properly called sharp. It's a positional sacrifice by black aimed at pressurising white's Q-side. The Benko is best played very positionally by white. The Modern Benoni is very sharp. The Dutch tends to be quite slow except where black goes g3 and white plays h4 h5 with an Exchange sacrifice.

The way I play against the Mar del Plata KID is to play Ne1, which is white's strongest move, and f3 and g4. That way, white tries to kill all of black's K-side attack and if white can get the Q and all the rooks off, which often happens, the ending is about 70-30 in favour of white.

One thing that can be pretty sharp is the Slav if black plays Bf5 to try to develop it, allowing cd and then Qb3. White has a thematic pawn push to e4 in some of those positions ... not really a sacrifice so much as a time gaining device to mount a Q side and central attack, since the pawn hits the Bf5 and forces a reaction.

I was playing a4 against them for years and doing ok but not great. I thought it was more important to put an effort into more-played variations. These days, since I hit 73, I've started to play into the Botwinnick with Bg5 and I always seem to win. Maybe I haven't tested tough opposition yet but I feel confident enough to play it in slowplay otb. I was quite suprised when I finally analysed it and found that black doesn't have so many good options as I thought.

But the 1. d4 ...e5 openings are really sharp. It's just that white is so much better but occasionally I've missed something and lost horribly. I favour 1. d4 e5 2. de Nc6 3. Bb4 Qe7 4. Bf4 lines. Black occasionally gets a result in blitz but in slowplay should lose every time. Don't know what they're called, generically.

The reason I do not consider the Englund Gambit "sharp" is because to me, sharp and stupid are not synonymous. The Englind is a 1 trick pony. White doesn't fall for your dumb trap and you are good as dead.

As far as your other post, good for you if you can keep up with all that Botvinnik theory. I am simplifying my Opening repertoire at 49 and entering my older years, not trying to complicate it. Trompowsky/Levitsky, Petroff, Dutch, French. No Botvinnik Semi-Slav for me. Played that from both sides back when I was 25.

Preach!

Yeah Black really is playing for a draw in the Botvinnik, it's just he can get it if he knows what he's doing.

Bf4, sorry.

I was hesitant about suggesting it but I did so because it's viable in fast chess among weaker players and moreover, some positions I've had when opponents play it are really very sharp and difficult to calculate quickly.

I didn't get the impression that the Botwinnick is all that theoretical. I played it a number of times in blitz against human opponents and found myself winning. Then it occurred against a bot and again, I kept getting the better position. I was rather surprised because I'd assumed it was ok for black, so then I tried to analyse it and I couldn't find many lines to improve for black on what was being played against me. White gets a pin on the N and takes with the pawn, so far as I could see. It isn't easy for black. White seems to get a pawn and white is still the one with the pressure. I haven't looked at any theory but I do have a 1980s book on the Slav somewhere.

By no means did Black play the "main line", but if his idea was to try to get me on time in a 3-minute game, figuring I wouldn't know what to do, he was sadly mistaking.

Here's what 1.d4 e5?? looks like:

https://www.chess.com/game/live/129408810801

I never played d4-d5 as black, so I dont know anything about those. But outside of that complex, I'd put my money on the modern benoni. Oh boy.

No-one's going to play 3. Bxf2 though.

Depends really at what you are looking; i think you can get sharp games from pretty much any system, but probably the ones that *tend* the most to be sharp are things like the Semi-Slav, King's indian, and Benoni, maaaybe the Grünfeld also. You also have some other options like the Benko, or some lines in the QGD (Vienna, Ragozin, Barmen, or probably just the exchange variation by istelf); however, i think these last one fall more in the category of "Dynamic" rather than "Sharp", but still (they can also get sharp too if allowed).

The Englund Gambit is the sharpest but is quite terrible.

The Modern Benoni is also pretty terrible if your opponent knows what's going on.

The Dutch Defense is very sharp and playable at the same time. A lot of my tournament games have ended within 30 moves with mixed results. Great opening if you are tired of Londons/Catalans/etc. I used to play this more often, but I've become more aware of my limitations as time passed and I grew older.

I was playing the exchange QGD with 0-0-0 for about a year but the problem with it is that it's overtly aggressive, which immediately dictates black's game-plan to him. He knows he has to defend on one side and attack on the other and so although I won some games and drew the others, it was harder going than I thought it should be, regarding the effort I had to use with white. I remember the last time I ever played it. Objectively, it was a superb game. Black successfully fended me off although I threw everything at the kingside but the result was that although it was even in material, I had a winning endgame because my king was already on the queenside. I remember feeling rather sorry for my opponent.

In the King's Indian Defence Mar del Plata, I always play the same strategy if I can. Play g4 to block the K side, which usually gives an open h file and an open c file. If the b file is opened instead, white seems to get a better advantage but that's up to black. Then get the queens and all the rooks off and use my three move advantage, which is the time it takes for black to get his bad bishop on g7 into the game, to create a winning queenside attack, where I win a pawn or sacrifice a piece to create a pawn overlap. White has one or two key moves on the Q-side, which create the maneuvring space needed to win. If a KID gets tactical then I get worried. I want to keep total control.

Black can't force a position to be sharp. White will have to cooperate. You can play something like the King's Indian hoping for complications, and if White plays in the most principled ways, you'll get them. But if White wants to play it real solid (e.g, with e2-e3 instead of e2-e4 -- and you see very commonly at lower levels) you have to be patient and be happy with equality. Maybe you'll get chances for a tactical shot later, but only after patiently improving your position.

This is, as best I can tell, true of all the potentailly sharp replies to d4 (and to e4 too, for that matter -- if you play a Sicilian below, say, 1500, you'll see a lot of sidelines (e.g., 2. Bc4), where you can equalize without trouble, but you don't get the opposite-side castling pyrotechnics you may be looking for.)