This one is very tough.
For Hero the key is all on the river, as a check/call on this spot is unusual.
So, for Hero:
- Exclude everything that is not a point (I don't see a check/call with A high or worse here).
- Exclude every Full House as I think they are just too strong to check/call the river, there's plenty of hands that can call.
- Marginal TcXc are an option. But the only ones that make sense for a call preflop and a check/raise on flop are A♣T♣ and J♣T♣. But we are on pretty marginal concepts here and regardless, AT would probably still be all-in on river.
- At this point we are left with Top Pairs that want to protect and get value on flop. Namely, KQs and AK. But it's hard to think an AK as a preflop call given we are on NL100. That probably would be a 3b/push.
So let's try with KQs:
Preflop: makes sense. Can be seen as both strong and speculative hand.
Flop: a bit marginal, but a check/call here would lead to so many troubles afterwards that it makes sense to raise, if you also have some backup plan as well (K♣Q♣).
Turn: bad card to barrel with a bluff, but good if we have value. The bluff-catching range of villain should be wider now and good draws still call.
River: it becomes way too thin to shove and we'd be called only by better hands. We are happy if villain checks behind with the bluff-catching range, and not too sad (depending on reads) against a shove, as busted draws here are a possibility. I have to assume there must be pretty aggressive players on NL100 and also stupid aggressive players that shove any busted draw regardless of how the board developed. We are also not afraid of AK because BU probably would have 3b it preflop.
So my Final Guess for Hero is K♣Q♣.
Now for Villain:
The key here is the combination of the bet/call on flop, with the bet being rather small, and the not-check-back on the river. We are in a 3way pot and if we have something like a set we want to get it in as soon as possible. Same goes with two-pairs on such a drawy board. Certainly it would be marginal, but it would also be even more marginal to check them behind or bet/calling with them, as two-pairs are rather vulnerable and there are a million hands you don't want to see on the turn.
What's left is draws and pairs.
No sense in bet/calling anything under a Top Pair here tho, especially considering the shove on river.
So the only Top Pair I see here that MIGHT not check/back river is AK, but again, it's an unlikely scenario and even more unlikely preflop, as it would have been a 3b most of the time.
What's left is draws.
Anything without a flush draw I think would have folded the Turn because of the dangers of both flushes and full houses.
I want to believe that Q♠J♠, J♠9♠ and 9♠7♠ would have been all-in on flop.
So it must be something more marginal but still good enough to bet/call the flop and call the turn and think to have implied odds for the river, considering the board is paired as well.
A♠9-2♠ feels too weak to call the turn as well.
9♠6♠ as well.
We are left with AQ, AJ, Q9, J7 all of spades.
They are all hands that would call preflop, maybe J7 being a bit too marginal tho (preflop and turn), so we remove that.
AQ would have been all-in on flop most of the time, as it draws to the nuts both for straight and flush and it's overall very powerful here.
A♠J♠ or Q♠9♠.
Good arguments for both of them, but Q9 not drawing to the nut flush on a paired board discourages it a bit more than AJ, even though the all-in factor on flop is relevant with this hand too and not only AQ.
It's a hand that generally looks much more appealing tho as it blocks powerful aces from Hero, if Hero is on total bluff we also have showdown value, and we are drawing for the nuts for both straight and flush.
So let's try with AJs:
Preflop: fairly standard.
Flop: obvious bet, and not clear all-in with a 3bet+, we can call this.
Turn: didn't want to see a paired board, but we still have so many outs against anything that's not a full house, and there are still plenty of hands like that, coming from check/raise on such a drawy flop.
River: a check like that shows weakness as we can check-back with all the worse hands, indicating lack of will to get maximum value, if we shove here I think we can make any Kx fold, considering that Hero probably would have 3b AK preflop. Shove.
So my Final Guess for Villain is A♠J♠.
Well, I don't know, there are holes in both theories but that's all I can come up with.
Hands:
Hero K♣Q♣
Villain A♠J♠