8-handed game, UTG opens to 3bbs, I'm UTG+1 and look at KK, I 3-bet to 10bbs, UTG+2 4-bets to 30bbs, MP 5-bets all-in with his 75bbs "shortstack".

It folds to us. Me and UTG+2 are playing deep, around 400bb effective stack. UTG+2 is an aggressive, competent player, he understands deepstack play enough and he definitely doesn't only have the nuts when he 4-bets. MP is a huge fish.

So the question is, what do we do with KK here? We're definitely not folding but should we call the 5-bet and invite the UTG+2 to join the pot and play postflop OOP or do we 6-bet to lets say something like 180bbs? We have the second nuts but I'm a bit worried that we might be isolating ourselves against AA and fold out everything worse which would be a disaster.

I decided to ---I EDITED IT OUT---

When I would 4-bet as UTG+2 and I would face a 5-bet and then a 6-bet I would probably just fold everything but Aces and Kings. I might even consider folding KK against some players when 400bb deep. So I think just calling with Kings was alright but I'm not sure, what do you think?
Cheers.

Don’t provide the results in your post.
It biases the answers of replies.
Personally, I don’t think flatting or reraising is a bad option here if you are comfortable playing a pot OOP deepstacked. Reraise is probably slightly better though.

You're right, I deleted the results.

I can play OOP, that's not a big problem, I just wonder how to get max value. I was also thinking something like "I will call the 5-bet, if I get 6-bet by UTG+2 I will consider a fold". But is it right to think that? I'm 100% sure we can eliminate all bluffs if this guy 6-bets here, it's pure value so we're up against KK and AA, 7 combos, 6 have us crushed. So I think I would fold.

I would personally only 6-bet Aces in that spot with no bluffs in my range against bad opponents who will call with KK always and just say it was a cooler. And I will flat the 5-bet with AA against competent players.

Think it's a fairly trivial flat pre with all of our continuing range. 5 betting looks super strong and we are are not getting that much action from a range of anything other than Aces.

Would be useful in this instance to know what the villain thinks of Hero in this spot. Does he think you are capable of folding KK to a 6bet? This would make him more likely to shove worse as a 6 bet as then he can freeroll vs all in player.

err...without reading this super closely equity denial is a huge thing here and Hero should iso fish. if it's AA<KK then so be it

He definitely doesn't know enough of my folding tendencies (and I actually fold a lot against many players there, they just don't bluff enough in many spots).

I'm pretty sure in this spot he's not even considering a bluff, I've played a lot against this pool of players and they can be aggressive but in huge spots like this I haven't seen a single bluff over many, many sessions. So when he 6-bets, I can be sure it's a value raise.

Yes, that's a fair point as well. Do you have a suggestion how I can weigh these two factors against each other to make a decision in the future? I mean equity denial vs isolating myself against a better hand?

It's a 400bb effective stack so fine, we can deny equity but do we really want to get all in for 400bbs with KK? Not sure.

If I 6-bet there to lets say 180bb and get 7-bet all in for 400bb I think I would want to vomit.

Bobby Hoff once said that if he had KK and he couldn't make a set, he'd rather have two cards from the muck. A 5 bet from a 1/2 player isn't going to be wider than KK, AK. I'm ok with a fold. If one of the villians shove on a J high flop, are you calling?

The UTG+2 guy had AQs and he called the 5-bet, the MP fish had 88. I won the hand at the end.

Anyway, the big question is - how to decide whether it's more important to:
- deny equity to hands exactly like AQs which has solid equity against KK
- or to keep the player's range wider and let him call with AQs and deal with the fact that 30% of the time he's going to get there.

While I agree in theory, with a 30bb raise and villain sitting on 75bb, he can't really flat. Which would make me think that he's probably wider than the worst case scenario. Again, completely different if Villain is sitting deeper and raises to 75bb.