Scandinavian Defense: Kiel Variation

One of White's main goals is to control the center of the board with their pawn on e4. This move allows White to gain control of the square d5, making it difficult for Black to establish a strong pawn structure. This also frees up the bishop on c1, allowing it to develop and potentially put pressure on Black's position. Additionally, this move prepares for White's future developments by allowing their pieces, particularly the queen and bishop, to enter the game more easily.

By playing d5, Black also aims to control the central squares of the board, preventing White from gaining too much space and forcing them to react to Black's moves. This move also opens up lines for Black's queen and bishop, potentially leading to strong attacks against White's position. By taking control of the center, Black can also build a solid pawn structure that can be difficult for White to break down. Finally, this move can also lead to a trade of pawns, simplifying the position and potentially leading to an advantageous endgame for Black.

By capturing Black's d-pawn with their e-pawn, White not only gains control of the central square e5, but also opens up lines for their queen and bishop. This move can also lead to a trade of pawns, relieving some pressure in the center and potentially leading to an advantageous endgame for White. Additionally, by opening up lines for their rooks, White can potentially generate strong attacks against Black's position. Finally, forcing Black's knight to move after the pawn capture can also limit Black's options and make it more difficult for them to develop their pieces.

In the Scandinavian Defense: Kiel Variation, Black's move Nf6 attacks White's pawn on e4, which is currently undefended. Additionally, this move develops Black's knight and prepares for potential future attacks on White's position. By putting pressure on the pawn on e4, Black can potentially limit White's options and create weaknesses in their pawn structure. Furthermore, Nf6 prepares for potential pawn breaks in the center of the board, such as d4, which can further disrupt White's position. Finally, this move can also allow for the development of Black's light-squared bishop, potentially creating additional attacking opportunities.

White's move d4 in response to Black's Nf6 aims to gain control of the central square e5, which is currently undefended and potentially weak. Additionally, this move prepares for the development of White's pieces, particularly the light-squared bishop, and potentially opens up lines for their queen. By establishing a strong pawn presence in the center of the board, White can limit Black's options and potentially gain an advantage in space. This move also allows White to potentially break down Black's pawn structure, leading to weaknesses in their position and opening up avenues for attack. Finally, d4 can potentially force Black's knight to move, limiting their options for future development.

Black's move Nxd5 in response to White's d4 aims to challenge White's central pawn structure and force a trade of pieces. By capturing the pawn on d5 with their knight, Black not only gains control of the central square e4, but also opens up lines for their queen and bishop. Additionally, forcing a trade of pieces can potentially simplify the position in Black's favor and relieve some pressure in the center. This move can also potentially lead to doubled pawns for White, creating weaknesses in their pawn structure and opening up avenues for attack. Finally, Nxd5 allows Black to develop their knight and potentially prepare for further attacks on White's position.

In the Scandinavian Defense: Kiel Variation, White's move c4 aims to further control the central squares of the board and potentially limit Black's options for further development. By placing pressure on Black's knight on d5, White can potentially force a trade of pieces, relieving pressure in the center and potentially creating weaknesses in Black's pawn structure. Additionally, c4 opens up lines for White's bishop on c1 and prepares for the rapid development of their knight on c3. Finally, this move can also potentially lead to a trade of pawns, simplifying the position in White's favor and potentially leading to an advantageous endgame.

Black's move Nb4 in response to White's c4 aims to attack White's queen and potentially force them to make an awkward move. By attacking the queen, Black can potentially disrupt White's coordination and gain an advantage in space. Additionally, this move prepares for the development of Black's dark-squared bishop and potentially opens up lines for their queen. By placing pressure on White's pieces, Black can limit their options and create weaknesses in their position. Finally, Nb4 can also potentially threaten White's pawn on c2, leading to further weakness in their pawn structure and potentially opening up avenues for attack.