The Systematic King's Gambit

Wield the power of the King's Gambit - the boldest, most brazen opening in chess!

If you are looking for fun and frolics in your game then serve up something special: the classic king-killer beloved of the greats.

You may not see it played at the very highest level these days, but that doesn't mean the King's Gambit isn't a vicious weapon a step or two down the ladder.

Let the battle royale commence!

The author, ajbobb, is a trusted Chessable community member who has previously published another course titled King's gambit: Punish your Opponent's Mistakes on this platform.

But The Systematic King's Gambit is a complete 500+ lines reworking from scratch with several improvements including:

👑 More lines (548 versus 259)
👑 Everything is checked with Stockfish 10 (rather than Stockfish 9)

The author devoted space to each branch and sub-branch that's proportional to how often those lines tend to be played by Black (click "More" below for more details) giving you a natural guide to what to focus on.

There is never a dull moment in the King's Gambit and this course takes you right into the action.

Start systematically chopping away at your opponents now.

A NOTE FROM THE AUTHOR:

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The King's Bishop's Gambit

Every White moves is the best possible move, per Stockfish 10 at depth >= 25, with one exception:

-After 1. e4 e5 2. f4 exf4, I prefer 3. Bc4!?, the King's Bishop's Gambit. Stockfish 10, at depth 36, prefers 3. Nf3, which is also by far the most commonly played move, and the difference in evaluation isn't trivial (-0.3 for 3. Nf3, versus -0.7 for 3. Bc4). My main rationale is that I simply love playing 3. Bc4. Opponents will be somewhat surprised when you play 2. f4!?, and even more surprised when you play 3. Bc4!?, which is played 8 times less frequently than 3. Nf3.

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Proportionality

When it is Black's turn, I included the most commonly played moves by Black, going from most commonly to least commonly played:

-For example, after 1. e4 e5 2. f4, Black plays 2...exf4 48% of the time, 2...d5 17% of the time, 2...Nc6 16% of the time, and so on. Given that the course has 553 lines:

--about 263 lines (48% of 553) start with 2...exf4

--about 93 lines (17% of 553) start with 2...d5

--about 88 lines (16% of 553) start with 2...Nc6

--about 60 lines (11% of 553) start with 2...d6

--about 44 lines (the 8% remaining) will start with other Black moves on move 2

--In practice, the actual numbers of lines aren't exactly what would be predicted (the actual percentages are 41%, 21%, 16%, 11%, and 12%, respectively), though I've tried to keep the proportions of lines in this book close to how often they are actually played in games

--This logic extends to sub-variations as well

-This procedure tends to create longer variations (longer line depth) for the more commonly played lines.

Thus, if you go through this course in order, you'll start with the lines that are most likely to come up in your games.

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Data, and Selection of Black Moves

I used data from lichess.org, using all publicly played games from all rating strengths and all time controls (1.21 million total games starting with 1. e4 e5 2. f4, as of July 23, 2019).

I included all Black moves that occurred in more than 100 games, and were at least the 12th most commonly played move, from the lichess dataset. I typically ended the variation when all remaining Black moves were relatively infrequent (i.e., all remaining Black moves had been made in fewer than 100 games in the dataset). The rationale for ending variations here is that there are diminishing returns to studying lines that rarely, if ever, have been played before. There are some exceptions in which I continued the variation:

-There is an interesting or seemingly obvious Black move which I want to be prepared to counter if it's played against me

-The logic of proportionality suggests I should include more variations from this branch. For example, after 1. e4 e5 2. f4 f6 3. Bc4, the most commonly played Black move (3...Nc6) has only been played in 97 games in the lichess dataset. But, Black plays 2. f6 0.5% of the time, so I want there to be 3 lines starting from 2. f6 in this book (0.5% of 617 lines). Thus, I include 3 options for Black on move 3 (3...Nc6, 3...d6, and 3...Ne7), choosing the most common Black moves that do show up in the dataset.

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Small Details

At the end of each variation, I included the Stockfish 10 evaluation.

I used the exclamation point (!) differently from how it's normally used. Black moves notated with a ! indicate the best Black move in that position (again, per Stockfish 10 at depth >= 25); these moves are not necessarily brilliant (i.e., they may be obvious). I never used ! for White because every White move is the best move.

One question mark (?) means Black's move worsened the position for Black by 0.9-2.0. Two question marks (??) means Black's move worsened the position for Black by >= 2.0.
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Enjoy!

Enjoy, and please let me know if you have comments, questions, or suggestions!