Lesson
White to move. Main line: 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Nxe4 5. d4 Nd6 6. Bxc6 dxc6 7. dxe5 Nf5 8. Qxd8+ Kxd8
The Berlin begins with 3...Nf6, attacking e4 instead of defending e5. White castles and permits 4...Nxe4 because 5.d4 opens the center with tempo and forces the knight to d6.
After Bxc6 and dxe5, the queens come off on d8. Black loses castling rights and has doubled c-pawns, but keeps the bishop pair and a compact position. White owns a kingside pawn majority and slightly easier development, yet converting those assets is difficult.
Do not treat the final position as an automatic draw. White’s plan is to develop, restrict the bishops and create a kingside passer; Black activates the king, challenges e5 and uses the bishops in the open center. Learning those plans is more useful than memorizing one extra branch.