Réti Opening: Réti Gambit, Keres Variation

In the Réti Opening: Réti Gambit, Keres Variation, the first move is 1. Nf3. This move isn't immediately aimed at occupying the center but rather prepares for a flexible development. This move also allows white to control the central squares indirectly, puts pressure on black's pawn in d5, and opens up the possibility of white playing d4 to occupy the center with a pawn. Additionally, this move doesn't restrict the movement of the f1-bishop, which may be developed later to control other central squares. In sum, playing Nf3 in the Réti Opening sets a solid foundation for the future moves and allows for a versatile gameplay.

In response to 1. Nf3, Black may consider playing d5 to occupy the center, gain control of the d4 square, and challenge White's indirect control over the central squares. This pawn move provides Black with an immediate stake in the center and allows for the development of the c8-bishop and potentially the f8-bishop. However, playing d5 also weakens Black's pawn structure and may make the d-pawn a target for White's pieces. In sum, playing d5 is a logical response to Nf3 for Black to gain space and control in the center, but it also involves a certain amount of risk.

After 1. Nf3 d5, White may choose to play c4 to advance a pawn into the center and control the d5 square. This move also opens up a potential attack on black's d5 pawn and allows for the future development of the c1-bishop and the queen's knight. Additionally, by playing c4, White prepares for a flexible pawn structure, where the c-pawn can be advanced to support other central pawns or exchanged to open up lines for White's pieces. However, playing c4 also creates a potential weakness on the d4 square, and Black may be able to occupy this square with their pieces. In sum, playing c4 is a common and practical move in many chess openings to control the center and initiate an attack.

In the Réti Opening: Réti Gambit, Keres Variation, after the moves 1. Nf3 d5 2. c4, Black may choose to capture the c4 pawn with dxc4. This move not only gains a pawn but also creates a central pawn majority and frees up the d8-bishop. However, the captured pawn may become isolated and weak, and its defense may require the movement of other pieces, which may impede Black's development. Moreover, by capturing on c4, Black allows White to occupy the d4 square with a pawn, which may give White additional control over the center. Despite these potential drawbacks, capturing on c4 with dxc4 is a common response for Black to promote a central pawn majority and generate counterplay.

After the moves 1. Nf3 d5 2. c4 dxc4, White may choose to play e3 to support the central pawn on d4 and defend the e2 square. This move allows White to complete the development of the d1-bishop and prepares for the future development of the f1-bishop, creating a strong diagonal for both bishops. Additionally, by playing e3, White controls the crucial f4 square, preventing a potential knight jump by Black, and prepares for a potential pawn break with d4-d5 to open up lines for White's pieces. However, playing e3 also blocks in the c1-bishop and may limit White's options in the center, making it more difficult to initiate an attack. In sum, playing e3 is a sensible move for White to strengthen their pawn structure and create a strong base for future moves.

After the moves 1. Nf3 d5 2. c4 dxc4 3. e3, Black may choose to play Be6 to attack the e4 square and relieve the pressure on the d5 pawn. The bishop on e6 also indirectly supports the d5 pawn and controls the long diagonal, limiting the scope of the white squared bishop. Additionally, this move helps Black complete the development of their minor pieces and prepares for potential central pawn exchanges. However, developing the bishop to e6 may also expose it to potential attacks by White's pieces and weaken Black's control over the central squares. In sum, playing Be6 is a natural move for Black to relieve pressure and take control of the center, but it also involves a certain amount of risk.