Here's a good video on how reading an opponent's plays can change the tides of a game. Not all cards are good to use when you think they are good to use, but sometimes it all depends on the situation you're in.
https://www.youtube.com/user/YGOTRADER101#p/u/7/6R3xjeUn_1wNow was it a good play, or was luck on his side, or maybe both? Personally I thought it was a great prediction, but he didn't account for the 2 other cards his opponent had in his hand. he could have easily reborned diva and went into stardust/trishula. then of course, you could say it was pretty late game and the chances of it being what the opponent needed was slim.
So anyway, here's a thread we can use for really ridiculous come backs or real situations you've been in or seen that could be good discussion.
