Live 3/5 9-handed NL game with $300 max buy in.

I am in CO with AsTs. Folded to me, I raise to $15 (pretty standard at this table).

Folds to BB, who calls. He is pretty bad, not too aggro or passive, just not an experienced NL player. Pretty much plays his two cards without giving much thought to what his opponents have.

Flop: KxTx4s He checks, I bet $20, he calls.

Turn: 3s He checks, I check. (I might be giving a free card to a draw, but this was mainly for pot control, and decent chance I am behind, but can win a big pot if I backdoor it.)

When I checked behind on the turn, villain was visibly frustrated, like he definitely expected me to bet. He grabs a stack of chips and quickly shoves it in. Dark bet $50.

River: Ks $50 to me, villain has ~$250 behind, I cover. He appears fairly confident upon looking at this river that he has already bet at. So obviously the most interesting card in the deck shows up, given villain's stack size I took quite awhile deciding what to do. If he has trips, I feel he will definitely pay me off if I raise. If he has a boat, he is definitely pushing to any raise I make. Just calling feels really weak, however. The question is, was he slowplaying top two or a set? Hard to say because the only hands I have seen him turn over were hands he bet the whole way, and none were monsters, just TPTK type stuff.

So,

Call, raise, push?

Given your description of the player, I think a raise on the river is +ev. Villain has trips here often enough.

I'd expect to see KT a lot here though.

If you know villain will call you with trips and push with a boat, I'd raise here.

I think he'd pay off a raise with trips as well. I honestly like you raising even more becasue you do hold a Ten, making it slightly less likely that he flopped top 2 pair.

If this player is bad, then a raise is +EV. A lot of players will act frustrated with top pair here because they see your check on the turn as confirmation that you just C-Bet the flop with no hand and they knew they had you beat.

He could easily have nothing here and be angrily bluffing, but raising is +EV.

This is where you wouldve gotten a good amount of info IMO had you put in a continuation bet. The fact that he s not a good player helps you out here as i think he would have a hard time slowplaying if he hit two pair on the Flop (K4).
If he did hit his two pair on the turn (K3) then you would most certainly get a reraise if you raise. but he checked it back to you to keep you in the game. Given the info and the 50$ dark bet i put him on KQ or AK at most giving him a set.

I d say raise and call the push.

He did c-bet the flop.