Find the decisive blow (difficulty 1395)

87654321 abcdefgh

White to move

Show solution
87654321 abcdefgh
  1. f6–e7 key move
  2. f8–e7
  3. f3–d4
  4. c6–g6
  5. e4–c5
  6. e7–f6
  7. c2–c3
  8. d5–g2

What makes it

A 1-point investment tears the position open and wins. One move, several targets — the fork leaves no defence. 8 half-moves of forced play.