Not really a "what would you do" hand, but a noteworthy bizarre play by an opponent. Setting: at my local, playing 1/2 NL. I've been there for an hour, slowly bleeding and topping up a bit, but just won a sizable pot to get me back slightly above even for the night. Two players sitting out. So six players in this hand. Two villains in this hand. V1 is UTG: Somewhat young guy. Just sat down a few hands ago. Looks to have about $240 after buying in for $250. Hero is in the cutoff. Stack about $400. V2 is button. Stack about $270. Middle aged asian guy who's been to my left the entire time. Seems solid, but not really tricky. Usually c-bets his raises, but slows down fairly quick. Seems distracted by his wife stopping by the table a couple of times to say god knows what in Mandarin or whatever. Hero is dealt Ts Th. Preflop, UTG raises to $10 Not having any info on the new guy, I flat. Button three-bets to $30. UTG calls the $30, so now I'm easily priced in to try and spike a set. I also call. About $90 in the pot. Flop: Td 5s 6c Well, hello there. Top set and a rainbow flop. UTG checks and I check also. Expected the button to c-bet, but he checks as well. Turn: 7s UTG checks but has an interested look. I decide to check as well, as I felt like the button was looking at his stack in anticipation to bet, and I'd love to get both players putting chips in before I check-raise. Button does indeed bet half the pot, $45. But no chance for me to check-raise, as UTG goes all in for about $160 more! Now this is 1/2NL, so it's not at all a consideration for me to fold here. Too many players at this level at this casino get it in really light. And at this point, I'm almost 100% certain I have the button beat, so I want him to call. I didn't really look to see how much he had, so I just call UTG's all in, thinking I have a better chance of the button calling if I don't re-raise. And he indeed does call. But only once the chips are cut out, do I see the button has only $10 left. Two red chips. River: 9c Final board: Td 5s 6c 7s 9c Yes, scary river, but no matter, given the pot and how much my opponent has left. Normally in this situation, I'd just toss in a green chip to put my opponent in, knowing it's call 100% of the time. But for for some reason, I instead announce all-in, with no move towards my chips at all. Don't know why I did it. And what happens next...well, to quote Jonathan Winters in It's a Mad, Mad, Mad, Mad World, "You just are not going to believe what I'm about to tell you." The button folds. You read that right. He folded to a $10 bet into a $700+ pot. Probably mathematically incorrect even if he only had king high. UTG shows pocket fives and I rake in a big set-over-set pot. Button looks down at his two red chips, turns them over like he doesn't know what they are. Button makes no comment and gets up to leave. My only guess is he thought he had $105. And that he thought my all-in on the river would have required him putting a lot more than $10 in. But I don't know. At the end of the night, I wished I had chased him down as he left and offered him $25 just to tell me what he had.