They must do?
If they are carbon, sentient, and functioning in this exact time/space dimension then they have very likely acquired at least some basic understanding of maths and physics. It is not far from there to game theory and games based upon randomly generated probability. Game theory IS nature and bound to be mapped out by anything following a similar evolutionary path of self-awareness using SCIENCE.
It might not look 100% exactly like Earth poker, granted. You’ve got to imagine there are some nuances that would apply across the infinite vastness of space and time. [Maybe they got rid of Jacks??]. But nonetheless a variant of nash based decision making using easily available materials that would also be relatively easy for poker players to learn and map out if they ever get the intergalactic memo.
Even if the best of the best (Bilzerian level) would be total cosmic fish versus their opponent species’ game. And vice versa.

There’s a lot of assumptions going on here.
I’m borderline serious though.

Maybe they play, but still haven't invented GTO yet

If they play poker, I bet there are some 3D game mechanics involved in terms of the way they imagine poker hands or maybe even the betting system.

I would guess that an alien poker HAND might be more or less than 5 cards - aliens would not necessarily have 5 fingers like we do!

Telepathy seems problematic too. Might have to wear tin foil to play online.

illegal aliens do play poker

Poker deeply connects to human biology and our current state of evolution. I mean things like:

- visual recognition
- manual skills
- achieving state of deep concentration
- competitiveness and strategic thinking
- ability to produce high quality cards
- ability to connect through the internet
- processing complex information in real time
- the need for possessing more and more

Aliens from another planet would have to be very similar to us to play poker. But maybe they developed something similar to poker that we have never heard of.

Surely any advanced species will have incomplete information games. Game theory is fundamental to how individuals behave with each other. The only exception to this would perhaps be hivemind species that lack the concept of an "other".

I doubt aliens play poker. The game is arbitrary, the number of cards in a deck, and the ranks/suits are arbitrary, the rules are arbitrary. But they would certainly have some type of incomplete information games, and concepts like wagering, bluffing, EV, exploitability, etc would be common.

Nash Equilibrium exists for most games - any game that has a finite game space and allows mixed strategies has at least one NE.

Would poker players be able to understand the game? I guess that depends where they are on the Kardashev scale. We could probably learn another type 1 civilization, but might not be able to comprehend a type 2+ civilization's games. No more than a particularly smart insect could understand double-board bomb pots. The intelligence scale is vast.

Sometimes I play poker in my dreams, so I think the game can be adapted into a new environment also, like other planet.

They certainly do.

The stakes are 1 earth / 2 earths. Minimum buyin 1 galaxy. A moon is raked out of each pot.

I think it all boils down to WiFi. Or the router. Or time. But on the time issue, I play retro games like Tetris; Sonic2; Chuckie Egg whatever. It is not inconceivable that an alien collective might consider deliberately downgrading its own ludicrous intelligence a la holadeck style to muck in with the 21st century 6max basic solver era grunts for the tourism verisimilitude?

Plus we tend to assume evolution is linear; but it might go backwards too.

They might be dangerously thick, post-ascension, and any interspecies interactive gaming is way too easy for the serious alien grinder to feel any sense of intellectual pride or achievement. Add in a society devoid of any financial incentives and this is an even bigger dilemma.
And we might be considerably better at lying than they are too. What we call poker they call Porkie$, a highly sought survival skill they've accidentally unwound with ubiquitous truthtelling. They are thus driven by their intergalactic existential necessity (IEN) to seek out our much prized 4 billion yr old bullshit technology (4BYOBT) before they all die off out of tedium.

When I think about the universe and making bets, I see this flop:

If you can avoid invading Mars ott that’s a great flop for IP

Tell me this guy's not an alien.

Everyone's worried about aliens killing us and taking over. Maybe they're already here exploiting our primitive understanding of zero sum games?

You can shear a sheep many times, you can only skin it once.

Nah, you can save, copy or whatever This thing has been mentally torturing me for exactly 20 years since the music I made in 2004. Finally I was able to FULLY visualize the whole thing. It's such a relief for my brain. Although I still need to make the official choice and pick the card, which actually isn't that easy

I'll have to bet my whole future on this card. It's like an intergalactic casino. I wish they had a poker game better than NLHE, too.

Yeah, I remember Tom Dwan complaining about the lights over the table after he bluffed Ivey in High Stakes Poker, if my memory is correct. That leaves a good trace for a conspiracy theory.