wow....what a close game
Biggest comeback in the history of competetive chess

Sorry but:
Your comeback was only to a draw
and
it was only because your opponent played very badly.
There are millions of games where someone dropped a queen in the opening for no compensation and won.
Of course it would help if you would define "comeback"
Black made some major blunders in that one. 66...Rg2? Instead 66 ... f2 looks like it wins. Black threatens mate with Rg1 and has a place for the King to hide at f3. But every game (at my level) has blunders. Good work saving that one.

Huge comebacks are always due to blunders from the favorite side. This come from game theory. Chess being about blunders and how to exploit them, this victory is legit ;)
GG OP :p

The problem I have with this post is the language inflation in the title. Do you really think it's the greatest comeback of all time? Seriously? Or is it just a blitz game where the side up in material failed to convert? Hundreds of those games happen every day.

The problem I have with this post is the language inflation in the title. Do you really think it's the greatest comeback of all time? Seriously? Or is it just a blitz game where the side up in material failed to convert? Hundreds of those games happen every day.
+ 1
comeback from a loss. A draw is better than losing.
Black made a mistake: he allowed white's passed pawn to get strong. This made the win much harder. (Black is still probably winning at this point (I think), but it's not trivial anymore.)

This is my game. I was white (LongTastySnake). I was losing by around 7 points in the opening-midgame, but the opponent blundered multiple times which led to my checkmate.
I would like to submit to you the biggest comeback in the history of chess. This was a 5 minute game, so obviously not the best quality game. You can see the opponent is significantly stronger than me and was putting a lot of pressure on my position right away.
You may say that you have seen bigger comebacks - I disagree! Usually these 'comebacks' involve swindling with some kind of fancy mating combo or stalemate trick.
In my game, I had 2 rooks and 2 pawns vs 2 rooks and 6 pawns. In other words, the simplest win imaginable for my opponent. Surely my playing on caused him great insult. When I drew the game I believe he probably committed ritual suicide in shame.
Thank you for your time! Here is the game :)