$2/$5, $1,000 effective stack
$10 UTG straddler. Hero in BB with As6c. Folds to hero. Hero raises to $25. Villain calls.
Flop is J33 two spades. Pot is $50
Hero bets $35. V calls.
Turn 2h. Pot is $120.
Hero bets $80. V calls.
Pot is $280. Hero has $960 left.
River 4d.
Hero?

My thoughts are my overpairs and best Jx like AJ and KJ want to overbet the pot to get max value versus Jx. But with this blind versus straddle configuration I'm going to have a lot more overcards and just total air, so I don't think it makes sense to take every hand I play here for a triple barrel even though it's a good board for Hero. OR since we have a range advantage it's just always a triple barrel and embrace the variance? I think most of the 2/5 player pool where I play would snap call JT and better unless I started betting 2x the pot or more. Even then they might snap call. It really looks like V has a J here and Hero doesn't know if V is willing to fold Jx for any sizing.

Holding the As you have a pretty bad hand to bluff.

Like if you're targeting Jx, good luck.

To go to the River question specifically: you block his likeliest call-call-fold hand (the nut flush draw), and unblock his likeliest call-call-call value hands (KJ, QJ, JT, J9, J8). This seems like a really terrible option to continue bluffing with--we need to have some give-ups, and this has to be one. Check-fold. (We could continue to bluff River spades and maybe some face cards on occasion...but not this offsuit 4.)

My only complaints with the rest of the hand as played are:

1) Your preflop raise should be a little larger, to at least $30. Treat it exactly like a SB vs BB situation, where your opening size should be 3x.

2) Your flop bet is too large. J33 is one where you get just as much fold equity with a small bet as you do a large one, so we ought to use the small sizing (with both our bluffs and value). This is even more true when you hold the ace of spades here--he's gonna call when he has a Jack or a 3 or a pocket pair, and fold everything else, and we can find out if he has those with a $15 bet.

Yeah, I don't like having As here. You can have every 5sXs, and 6sXs which block 6s5s and As5s and have no showdown value. You can also have some hands that might block boats like 54s, 42s blocking 43s and 32s, but would need to bet flop with no backdoor flush draw. Those might be good check raise bluffs for very large sizing.

I would think your straights would also want to overbet, maybe even your 3x. So I think your main river bluff size is probably going to be something like 150% pot. Not something I looked up in solver though.

Preflop, a subtle thing, but you should raise at least 3x out of position to the straddle. In button and earlier, 2.5x is fine.

Also, you can have a mixed strategy of completing and raising preflop in BB vs straddle, and this is a good hand to complete. You would need to have a sound complete-reraise strategy though with strong hands.

i think you're going to get a more efficient bluff with smaller sizes. the issue with going big on every street is you're going to filter him down to where he really only needs to call with Jx. a large component of bvb is their range is so wide you're challenging uncomfortable parts of it with small bets early

Not every line works. Time to give up.

I gave up and he checked back Jh8h.