Lesson
White to move. Main line: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Ba5 6. d4 exd4 7. O-O d3 8. Qb3 Qf6 9. e5 Qg6 10. Re1 Nge7 11. Ba3 b5 12. Qxb5 Rb8 13. Qa4 Bb6 14. Nbd2 Bb7 15. Ne4 Qf5 16. Bxd3 Qh5 17. Nf6+ gxf6 18. exf6 Rg8 19. Rad1 Qxf3 20. Rxe7+ Nxe7 21. Qxd7+ Kxd7 22. Bf5+ Ke8 23. Bd7+ Kf8 24. Bxe7#
The critical position arrives after 19...Qxf3. Black appears to have won White’s queen with check, but 20.Rxe7+! removes the defender on e7 and forces the black king into the bishops’ lines.
After 21.Qxd7+!, the queen is offered to drag the king onto d7. The bishops then coordinate the checks: 22.Bf5+, 23.Bd7+ and 24.Bxe7#.
Unlike a puzzle that starts at the combination, the full score shows why the combination exists. White’s lead in development and open files were purchased by the Evans Gambit long before the final sacrifices.
The other Anderssen masterpiece
Played against Jean Dufresne in Berlin in 1852, the Evergreen is the Immortal’s quieter twin: the same attacking instincts, but the combination at the end is exact rather than romantic.
The name is traditionally credited to Wilhelm Steinitz, the first World Champion — the player who would later build the positional school that made this style of chess much harder to play.
The finish is the lesson
The concluding combination works because every black defensive resource is answered by a check. Black is never given a free move to bring a defender across, which is what makes the sequence forced rather than merely strong.
This is the practical difference between the Evergreen and the Immortal. The Immortal persuades; the Evergreen proves.
A forcing line is one where the opponent never gets a choice. Count checks and captures first.
An attack against an uncastled king is a race you are already winning — the extra tempo is your material.
Combinations end games; the moves before them are what create the conditions.
Source: The Evergreen Game — https://en.wikipedia.org/wiki/Evergreen_Game
Source: Jean Dufresne — https://en.wikipedia.org/wiki/Jean_Dufresne