KGD - 2...Nf6

The KGD 2...Nf6 chess opening, also known as the King's Indian Defence, is a popular choice among chess players. It begins with the moves:

1. d4 Nf6

Here are some reasons why to play it:

1. Counter-attacking nature: The King's Indian Defence is known for its counter-attacking style. Instead of immediately challenging White's center pawns, Black allows White to build up a center and then aims to attack it with piece play and pawn breaks.

2. Complex positions: This opening often leads to complex positions with a lot of tactical and strategic possibilities. If you enjoy complex middlegames and have a good understanding of chess strategy, this opening could be a good fit for you.

3. Used by top players: The King's Indian Defence has been used successfully by many top chess players, including former World Champions Garry Kasparov and Bobby Fischer. This means there are many high-level games available for study.

However, there are also reasons why to avoid it:

1. Requires deep understanding: To play the King's Indian Defence well, you need a deep understanding of chess strategy and tactics. It's not an opening that you can learn quickly or play successfully without a lot of study.

2. Risky: The King's Indian Defence can be risky. White often gets a space advantage and a strong center, and if Black is not careful, White can launch a devastating attack.

3. Long-term defence: In some variations, Black has to defend for a long time before getting a chance to counter-attack. If you prefer openings where you can take immediate action against White, the King's Indian Defence might not be the best choice.

In conclusion, the King's Indian Defence is a complex and strategic opening that can lead to exciting and challenging games. However, it requires a lot of study and understanding, and it's not the best choice for everyone.