A brilliant move is simply the best move in the position that is also hard/tricky to find, it specifically says so if you highlight the word brilliant on the report section of the analysis board. Maybe there are more complicated or technical definitions but they are not really necessary for practical purposes.
Brilliant Moves in New Game Analysis Report

I have had 1 brilliant move in all of the games I've played. Unfortunately, in the very same game I also had 2 Blunders!! Oh well . . .

I have had 1 brilliant move in all of the games I've played. Unfortunately, in the very same game I also had 2 Blunders!! Oh well . . .
Not to mention that your brilliance was probably accidental 😀

A brilliant move is simply the best move in the position that is also hard/tricky to find, it specifically says so if you highlight the word brilliant on the report section of the analysis board. Maybe there are more complicated or technical definitions but they are not really necessary for practical purposes.
Hi @Graber7,
You are right for the "hard/tricky" part but here is a consideration you should add to your practical set of ideas:
The engine analysis will never suggest a move and call it "brilliant"
This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move.

I think the bottom line on brilliant moves is that it is a meaningless stat. Some programmer tried to program a computer to understand the difference between a logical best move and a best move that goes against normal human instinct. Computers can't make that differentiation.

It's probably a game played with an assistance of an engine but who cares since it's unrated mode against another computer. There is no point to forbid an help from another engine in this case.
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This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move.
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That doesn't make any sense. How would the engine know that the "brilliant" move is better than what the engine considers best? Do you have any evidence?

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This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move.
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That doesn't make any sense. How would the engine know that the "brilliant" move is better than what the engine considers best? Do you have any evidence?
Because what the engine thinks is best is not set in stone, it's often the case that playing a better move than the one suggested changes the evaluation of the engine and if you go back to the original position it'll now suggest the move you played.
There's also the (obvious) fact that it'll* change it's move choice as time progresses.
*OFC, not always.

Don't know if anybody else has mentioned this, but I find a lot of times, you do the initial analysis, it reports zero brilliant moves, but then when you go through each move, it reports some as brilliant.
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This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move.
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That doesn't make any sense. How would the engine know that the "brilliant" move is better than what the engine considers best? Do you have any evidence?
Because what the engine thinks is best is not set in stone, it's often the case that playing a better move than the one suggested changes the evaluation of the engine and if you go back to the original position it'll now suggest the move you played.
There's also the (obvious) fact that it'll* change it's move choice as time progresses.
*OFC, not always.
You're missing my point: we are talking about the final evaluation of the analysis feature on this site, not an ongoing (changing) calculation.

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This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move.
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That doesn't make any sense. How would the engine know that the "brilliant" move is better than what the engine considers best? Do you have any evidence?
Because what the engine thinks is best is not set in stone, it's often the case that playing a better move than the one suggested changes the evaluation of the engine and if you go back to the original position it'll now suggest the move you played.
There's also the (obvious) fact that it'll* change it's move choice as time progresses.
*OFC, not always.
You're missing my point: we are talking about the final evaluation of the analysis feature on this site, not an ongoing (changing) calculation.
Then it'll likely tag it's best move as brilliant for other reasons, the reality is that nobody is sure what "brilliant" means here.
Then it'll likely tag it's best move as brilliant for other reasons, the reality is that nobody is sure what "brilliant" means here.
I'm sure the programmers do know, but you're right, we can only guess. But anyway I stand behind my original argument that the statement
"This is because "brilliant" is a move by the player only assessed by the engine to be better than what the engine would suggest as "best" move."
doesn't make sense.

In Lucas chess there is a similar feature. A move by move game analysis shows the evaluation after each move. Normally you can only maintain your level of advantage by playing the best move. Sometimes however, the computer evaluation goes up after your move, meaning your position was better than it originally calculated. In other words you found a move that was underestimated initially by the computer.
I've played around 1000 games and have yet to have a move considered brilliant. You would think I would have stumbled onto one accidentally by now.