White blundered the fork, but luckily has one line to keep things equal. What is it?

FINALLY

Took me an absurd number of games. I have no idea what time format the bot’s elo is based on, but it sure is strong.

Why was this a blunder?

What's the meaning of these numbers that I've highlighted?

And why are the 22nd and 23rd move numbered differently? This is from analysis on Lichess.

Why is this marked as brilliant ? I pressed show moves and I don’t see anything good.

What the martin doing

Made a plan to trap their Knight, and pulled it off!

Find the best move for white!

I know these posts have become redundant but can someone tell me why this move is brilliant?

What is the tightest game of chess you have ever won?

[BLACK TO MOVE] From my most recent game