5.Re1 Nd6 6.Nxe5: the main line is variation 2 of 6 in the Berlin Defence course, a advanced opening course for Black (ECO C67). It runs 26 moves and begins 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Nxe4 …. White attacks the e4 knight with the rook. Black retreats to d6, and after the trades on e5 both sides castle. Black puts the bishop on f6, challenges the e-file and gets a solid, equal game. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. e4 – White takes the centre.
1... e5 – Black claims an equal share.
2. Nf3 – White develops and attacks e5.
2... Nc6 – Black defends e5.
3. Bb5 – The bishop attacks the defender of e5.
3... Nf6 – The Berlin. Black attacks e4.
4. O-O – White castles and offers the e4 pawn.
4... Nxe4 – Black takes the pawn.
5. Re1 – The most popular move. The rook attacks the e4 knight at once.
5... Nd6 – The knight retreats and attacks the b5 bishop. It also guards c4 and f5.
6. Nxe5 – White wins the pawn back. The knight hits c6 and f7.
6... Be7 – Black develops and gets ready to castle. The bishop also blocks the e-file.
7. Bf1 – The bishop goes back home. There it is safe and guards the king.
7... Nxe5 – Black trades off White's strong knight.
8. Rxe5 – White takes back. The rook stands in the middle of the board.
8... O-O – Black castles. The king is safe now.
The lesson goes on for 10 more moves, each with its explanation.