Just wanted to add a couple of things: the game is Street Fighter 3rd Strike, where you can die due to chip damage. What this means is that even if you block special moves (like Justin’s Chun-li did) they still do damage, the aforementioned chip damage.

So Daigo Umehara, the Ken player, had no option other than parry or he would lose the game and Justin Wong, the Chun-li player, would advance to grand finals. Parrying in 3rd Strike is done by inputting forward as opposed to blocking which is done by inputting back. More specifically you have to press forward in a 10 frame window. Since 60 frames equal a second, you have a window of 1/6th of a second to input it and you also cannot hold forward, otherwise you won’t be able to use parry for the next 23 frames.

So if Daigo had held forward to parry the remaining hits of Chun-li’s attack, he’d die from chip damage (I think). What he did instead was manually parrying every single hit of the attack AND he also parried the attack in the air, which is even harder to do because in the air the frame window is halved (so you have a 5 frame window, or 0,5/6th of a second if my math doesn’t fail me), which doubles the difficulty.

And just to add to this: Daigo had actually done it in a match before but it wasn’t recorded. Also, the number 37 was chosen at random to make it seem as if there were a lot more hype moments like this. Also also Justin Wong, aside from being one of the best fighting game players of all time, has always been (as far as I know) a cool sport about this, even encouraging people online to do the Daigo parry whenever he plays 3rd Strike just so players (the ones who know how to do it at least) can sort of be a Daigo for a moment.

If you want to know more, I suggest this video: https://yewtu.be/watch?v=36m-teYaQmE

P.S.: Daigo would go on to lose in the grand finals. But nobody cares about that, to be honest. I don’t even know who won it.