I'd still 3bet pre. As played, I think it's a fold on river. He has a boat.

I do agree you can't 3bet/5bet shove, but I still think there is room to 3bet here, after all, the reg has a 0% 4bet over 400 hands so I don't think we have to fear getting 4bet. What are his fold to 3bet stats? They are a good indicator of how much value there is in 3betting, and will help you out in these spots a lot. If they're reasonably low then you're missing out on a lot of value by just flatting here.

As played calling the c/r is fine, if he is capable of bluffing draws, then this will be a spot where he will be bluffing, so just call him down and reevaluate based on the turn/river. But like you said, there aren't that many good runouts so you'll probably just end up checking it down.

The 8 on the turn is one of those bad runouts and now you only have showdown equity. Good check.

When the 4 hits its a really sick spot, but against an overbet I would have to fold. This type of bet really polarizes their range between either the nuts or air, but the problem here is a lot of the effective air from the flop c/r will have hit some part of this board e.g. 89, A5cc, T9 and henceforth, if its just a straight/two pair they'll bet a more regular sizing, but if its a boat they'll overbet like they have here. Essentially, I can't see there being enough air (which hasn't hit) in the opponents range to make a call profitable.

its either a boat or a combo draw that missed such a 8/9 or 9/10 of clubs. I actually think with the sizing on the river that he had a combo draw that missed as he knows that u cant call on the river as your hand is pretty much face up at this point.

pre i'd play the same,and i would snap fold the flop!hes had all nutted hands in his range...