Beat the King's Gambit as Black!

4 e5 Nh5 5 Be2 is okay for White, if played correctly.

and Carlsen, Kasparov, et al even played 1 e4 e5 2 f4 exf4 3 Nc3!?

As for the engines, I think it'd be asking a bit much to expect an advantage for White. They generally favour Black. The most they'll concede is that White is okay for a draw with best play. But in practical terms that's okay for me as a non-professional: if things go wrong White can still draw; and if things go well (which they often do) then...

I read years ago that the Kings Gambit might be a forced win for black. I wonder if the experts ever figured out if black could always win against the king's gambit.

No one serious is going go through all the possibilities of white and black as it cant even be done. There are now thousands of different engines with different moves.

If someone wants to play the Grob or KG vs me thats fine by me.

You are right

Isn't 3....g5!! the best move against King gambit?

Afaik, many King gambit variations in TCEC computer chess ended up lossing for white. 

The popularity of king gambit has declinded significantly since 1970s, not that useful for today preparation.

This is what I've been playing recently to deal with the Kings Gambit!

3 fxe5?? loses immediately tp 3...Qh4+.

@kestony King's Gambit is OK at your level for white well at any level it is but not the hardest opening to equalise with black.... but in blitz it's quite easy for white to play if black accepts at most levels

falkbeer counter gambit is black's best performing reply against king's gambit, but for some reason, I USED TO eat falkbeers up. now I see my stats aren't as good as they used to be.

the variation that drives ME nuts as a KG player though is 3...Be7, the cunningham, because it trades off my f3 knight I want to use to get at f7, but it also steals castling rights and hems white's rook in, SERIOUSLY ruining my plans. no one plays it, but I hate it MORE than falkbeer

my stats in that are the worst at 40:60 in 20 games. if you really learn it, you'll have surprise value too

Don’t play 2…exf4

Delaying the capture by 1 move can set up a deadly trap which some people fall for.

They should develop the Knight, but sometimes people take the e5 pawn with F pawn or try to push F pawn passed which is blunder.

I don’t see the harm in delaying the capture by 1 move.

It also set ups a trap in the process so I think it is better.

nah aa lot of people will castle and gambit more

The harm is playing ...d6.

Best is 1.e4 e5 2.f4 exf4 3.Nf3 d5! 4.exd5 Bd6 or 1.e4 e5 2.f4 d5 3.exd5 exf4 4.Nf3 Bd6

Both are the same position.

One advantage to the Falkbeer move order is it avoids the line 1.e4 e5 2.f4 exf4 3.Bc4 d5 4.Bxd5. He would have to go for the 4.exd5 line via 1.e4 e5 2.f4 d5 3.exd5 exf4 4.Bc4 (instead of 4.Nf3).

I personally would endorse the idea of using the Falkbeer move order to get direct to the Modern Defence; as per

Speaking as one who has long loved the KG from the White side of the board, I would counsel caution when it comes to playing 3..., g5 lines against the King's Knight's Gambit. It's the move which I consider objectively best from amongst Black's many options and it's the one which I play myself on the rare occasions I allow a KG on the board when I have the Black pieces, but it requires a shedload of learning. If you're thinking of playing 3.Nf3, g5 you probably need to fully understand the right lines against...

- The Kieseritsky; and

- The Allgaier; and

- The Rosentreter; and

- The Quaade; and either

- The Salvio and Muzio and Double Muzio and McDonnell and Ghulam Khassim and Lolli; or

- The Greco-Philidor and Hanstein.

All of these have multiple sub-variations too. For example in the Allgaier Black needs to be aware of at least four possible White moves from the following position and actually understand what to do about them...

From there, Bc4, d4, Nc3, and Qxg4? all need to be known about because the play diverges in each case and even the refutation of the questionmarked busted move needs learning (I'll give you this one: the bust involves ..., Bd6 and - I kid you not - it goes by the picturesque name, "The Horny Defence").

If you have a passion for the Black side of the KG and oodles of time available for opening study, 3...,g5 is your badger and no mistake. Otherwise, there's simpler ways to have at us old-fangled gambiteer types which don't involve cloistered weeks of delving into Nineteenth-century position themes followed by an emergnce; blinking in the unaccustomed sunlight; wondering whether Gladstone or Disraeli will win the forthcoming election, and pondering whether or not the repeal of the Test and Corporation Acts would be a good thing.

I play the Fischer Defense.

I don’t like playing d5.

The main move is d6 in Fischer Defense line.

@Compadre_J highlights a very good defence indeed for Black. KG players hate it (although we often don't admit that in public). Back in the 1970s, KG players were desperate enough as to start analysing 3..., d6; 4. h4?! Which doesn't really work but mixes things up and is good for a giggle in Bullet because it's usually good for ten seconds on the clock. Will Black spot ..., Nf6 - h5 - g3 and/or work out the tactics involving ..., Be7 xh4+? Who knows?

I don't approve of that sort of stuff myself - I see chess through a lens akin to that of Botvinnik (the art of making logic beautiful), but we're all different.

The trouble is that @ThrillerFan also recommends a very good line against the KG and one cannot play both lines at once. My own advice to people looking for a good line against the KG as Black is the same as my general opening advice to everyone. Have a look at what positions the lines lead to. In which of them are the good moves natural for you? When you find the line leading to that sort of position, Play That!