You've already mentioned Marshall's Qg3 move.
Reti's Be8 against Bogoljubov at New York 1924... although the breakthrough with the center Pawns (earlier in that same game) was equally impressive.
Which is the most famous Chess move ever played?
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There are some great sequences and games are remembered for the whole sequence, like Lasker's famous King walk.
However some games become famous for that 1 move, that seems mental and yet leads to a winning position. There are two such moves that I think of -
Shirov Bxh3 vs Topalov, which has widely been said to be the greatest move ever played & Marshall's Qg3 vs Stefan Levitsky.
Are there other such games where that 1 move became famous?