One topic I often come back to here is opening preparation in the age of the computer and the consternation caused when the opponent manages to catch you in the grip of a "centaur" - their collaboration with a chess engine.
Of course sometimes it is a human idea which you then examine with the machine's help, but sometimes it is simply an idea of the machine itself.
The latter can be particularly discombobulating because they produce moves which people really wouldn't think of - I suppose that since they are the "horsey" part of the creature, it is their hooves that do the damage.
I'm revisiting some old chestnuts today but starting with a game played last month in the final of the Grand Chess Tour, in which Fabiano Caruana uncorked a novelty which - at least to my human eyes - was very surprising even if it may not be if you think logically. Can you guess what Caruana and his minions had prepared?

Fabiano Caruana facing Wesley So at the recent Grand Chess Tour Finals in Saint Louis | Photo: Lennart Ootes / Saint Louis Chess Club
There are so many examples of opening surprises, deadly and otherwise. For my first I'm going to one which I may have used fairly recently in which Hikaru Nakamura (and friends?) played a ferocious novelty against Sergei Karjakin.
And I'm finishing with the granddaddy of them all: Frank Marshall's Gambit (or Attack if you prefer), which the American introduced against José Raoul Capablanca with very high hopes in New York 1918 - but lost with even so.
(Normally I would have made a video but nice MRXSplit is demanding that I use one of their standard log-in methods – i.e. Google, Apple or Microsoft - rather than my normal email which I've always used before and my account is tied to. How tremendously helpful!)
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