Pre-flop I would fold A10os to an UTG raise. Against a normal villain UTG raise you are likely either dominated (AJ, AQ, AK, 10, JJ, QQ, KK, AA) or flipping a pair (99 or lower). At best you are a slight favorite (KQ, KJ, QJ). Even if villain is a complete maniac, do you think he is raising UTG with two unpaired cards below a 10? If you were suited I could see maybe making the call. If you were the BB I could see making the call.

On the flop I would probably call. Yes you have an overpair to the board, but villain showed strength preflop so I’d want to pot control here. I suppose if villain’s aggression also includes 100% c-betting you can make an argument for a re-raise, but the fact that he is UTG makes me lean toward a call.

But once he 4-bets jams, I would fold. You started the hand with a lot of chips. Do you really want to put your entire tournament at risk on one pair to a player who has shown this much strength? In this case it worked, but I think against most opponents you would be beat as played.

I will say that his bet sizing is really strange. If he is consistently raising 3x-6x I would wait for something better than A10os to go to war with. Other things that it would be helpful to know. Is he just aggro pre-flop or is he equally aggro at every street? Is he aggressive from early position as well as late position or is he mostly aggro in middle and late position given that this hand he is UTG? Are you in the money yet?

I get that he is aggressive and you want to play back against him, but I’m not sure you had the hand to do so pre-flop. Post-flop I think there is a case to be made for staying in the hand, but I would have preferred a more pot controlled approach rather than re-raising him (although maybe he doesn’t allow you to keep it small on the turn or river). Unless he is jamming every hand he gets involved in, I think this was too big a pot to commit to with A10os.