Kenilworth Kibitzer

I was drawn to the story of Yacov Murey from the unconventional game Murey v Shirov 1993, in which Shirov praises Murey's creative thinking in chess.  Murey was one of Korchnoi's seconds in his world championship match in 1978, and ultimately became a grandmaster in 1987.  He might be best remembered for a shocking novelty that Murey unveiled on move 4 (!) of a well known line in the Petroff, after:

1. e4   e5

2. Nf3 Nf6

3. d4   Nxe4

4. Bd3  Nc6!?

This 'natural' developing move looks ridiculous at first sight - a piece is hanging on e4, after all.  However, after 5. Bxe4  d5  it becomes clear that White will have to return the piece in one form or another.  In the stem game which introduced 4...Nc6,  Timman v Murey 1993, Timman nevertheless chose 5. Bxe4, and after:

5....  d5  

6. Bg5 (now the main line) Qd7 (Qd6!?)

7. Bd3  e4

8. O-O!?  f6

White kept a small edge and nevertheless won the game.  

White has three other choices after 4....Nc6, including 5. dxe5, 5. Nxe5, and d5.  Amazingly, in all of these Black has good chances to equalize!  

A few sample lines:

5. dxe5   d5  (to me the most principled, but ...Nc5 is also played)

6. O-O   Bg4     (6. exd6 ep leads to an equal, virtually symmetrical position)

7. Nc3   Nxc3

8. bxc3  Be7     and Black scores reasonably from this position

5. Nxe5 Nxe5

6. Bxe4  d5    (6. dxe5 Nc5 keeps more asymmetry in the position)

7. dxe5  dxe4

8. QxQ+  KxQ

was the start of Shirov v Timman (!) 1998, going straight to an endgame which Shirov duly won in classic style.  But it is interesting that Timman was impressed enough by Murey's novelty that 5 years after seeing it from the White side of the board he was willing to try it for Black.   

5. d5!?  Nc5   (has White nevertheless refuted Black's play?)

6. dxc6  e4

7. cxb7  Bxb7

8. Be2  exf3

9. Bxf3  Bxf3

10. Qxf3

With a slight advantage for White though with limited attacking prospects; Raetsky and Chetverik suggest this as equal in their rather drab manual 'Petroff Defense'.

That Murey could conceive of this move in a pre-computer era, independently evaluate all these plausible moves for White, and then play the move for the first time against a top class opponent rates him in the pantheon of the coolest customers on the board.