What adjustments, if any, should I be making against an opponent who never ever raises pre-flop?

There are at least three players in the room I frequent that this applies to. They simply don't raise before the flop. I've seen them play AA and KK by limping in from any position, just cold calling a raise, etc. it's just bizarre. Even most super passive players raise AA, but these don't even do that.

They are obviously pretty easy to play against in general, but I'm curious as to how folks here would think about how to handle them, and also how many players you have come across like this.

make sure to keep them happy and in the game for lots of hours

do they ever bet/raise postflop without the nuts?

Heh, only 3? There are a bunch of them at CAZ's 8-16. A common characteristic is that they are also very passive if the flop looks scary to them, i.e. they have red AA and the flop is something like 10-9-8 double suited. So if they get active post flop you can fold everything except your strongest hands/draws.

Get a baseline on each of them: Make a mental note of how they play their big pairs post flop. It should generally be the same each time and you'll feel better folding some of your marginal hands.

You should try to get a handle on how loose or tight these players are preflop, and whether their passive preflop play translates into similarly passive postflop play. In particular, it would be helpful to know if these players will limp/call AA or KK and then donk "safe" flops, or if they tend to just check-call unless they have a true monster.

These players are losing money by not raising preflop with their big hands. Sometimes they will get to showdown and you will call them with top pair and they will proudly flop over their AA and you lose - that's OK, that will happen. But also, they will lose to you with two pair that you hit with 72o in the BB. When they happens they will get upset and wonder why AA never holds up. That's where they are losing lots of money - in pots they just gave away by not raising preflop.

The only adjustment during the play of a hand is to give them a slightly wider range, but otherwise, as other posters have said, look for their pattern with their big hands. For instance, I know of several in my game who won't raise preflop but will check-raise the flop with an overpair. For those players, I'm much more cautious about a flop c/r than I would be against other players.

In general you should

1) Attack less, because their limping range is generally stronger than average (after all, if they limp all the cards they plan to see a flop with, then their range is uncapped)

2) Be wary of post flop action; these players love "trapping", so they won't OL 87s pre and x/r T94r. Your AT has fold merit.

3) Fastplay value hands. As they congratulate themselves for inducing a big pot w/ AA, and x/r the turn on JT3-2, be sure to crush their soul w/ your JT (that you would've folded had they just raised preflop). Nothing like a cracked pair of aces to steam a fish.

How many hands are they playing? In other words, are they tight-passive or loose-passive?

I used to see these types of players all the time at 2-4 limit (when I used to play 2-4 limit), but some of those players probably just wanted to see $2 flops so they could get a cheap chance to win a jackpot. And it was just 2-4 limit.

In my games, if they flop an over pair they play it fast...so never slow play two pair or better. Go for free card raises less. Perhaps forego a value raise with a draw if this player lead into a MW field and is to you left, since he could 3b and possibly knock out your customers(unless the field is super loose and will call anyways)

If they flop a set, they almost always slow play. Be careful on dry boards. They usually don't peel lightly so it may be a trap. Consider value checking more against them.

A lot of these types only raise the flop with top pair top kicker or better.

They also seem to b/3b flop in rhythm and tend to play on auto pilot once they've flopped the over pair.

Semi bluff less against them, unless they are tight weak, running bad, think they play well by making hero folds.

It depends on how many of these ultra passive players are at your table and where they are with respect to you.

If everyone (but yourself) is super passive then raising with marginal values will tend to build a pot and you will have a difficult time knowing where you're at because the passive players are "speaking a different language" than you.

If the passive players are to your right and the tighter players are to your left then there is more of a reason to go ahead and raise with normal raising values as you should give yourself a good chance to buy position.

And in the case that one of the tighter players comes in behind you then you better hit the flop hard or be done with it.

Additionally, how loose are the passive players behind you assuming an entirely passive table.

If they are super loose then raising for value and trying to gain position won't work as well and will build a big pot with many opponents.

Does this mean you should just limp with AK or JJ and take a look at the flop?

I don't think so, but you might ratchet back your raising range and just call with KJs and 77 for pot control and deception.

Narrowing your raising range does give your opponent's a better chance to identify what you're holding but if they're that weak in the aggression aspect of the game, maybe they're also weak in the observation area as well.

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