Lately I've been curious about the possibilities in AH.

Namely what's the the longest a game can run (in game turns) , using the maximal set of circumstances.

From what I've found on these forums one poster's game ran for 33 Mythos cards!

I wonder if there is a way to mathematically determine this, and if not, can other players provide an idea of their longest game (turns or Mythos cards)?

I suspect that the shortest game is not much of a challenge especially with KiY.

Hi Nameless,

I'm the 33 Mythos player (or, at least, one of the 33 MP). That game was an experimental one, using only Kingsport board as additional board and using Mythos from every small box expansion having gate bursts in the Mythos deck (which means Black Goat & Lurker). This forces all activity to be focused on the main board, and it was a nightmare keeping all gates sealed. In fact, I had to coop for a closing victory, otherwise it would have been impossible do beat Eihort (some AOs would have been probably been easier and the game could have lasted some more time). It was a nightmarish game, I had to play three evenings for completing it (there is even a session report somewhere on this forum, if you'd like to read the chronicle).

Longer games are certainly possible, it depends heavily on the way you mix boards and so on. Wanna have something neverending? Play against Atlach with just the main board. And feel free to use Patrice, Roland and Hypnos, just to be sure you have enough clues to constantly seal everything (in this way, you'll be able to control very well Atlach doom track). This can go on and on forever

Yeah, it's possible for a game to go on indefinitely; if you had some seals and only drew gate bounces from then on (and, periodically, "The Story Continues..."), but uh a team that doesn't win given infinite turns is probably doing something wrong

Longest game possible is infinite, made possible with Ashcan Pete for one instance (though there's many other instances)

Shortest game possible is 0 turns (just the initial Mythos card). These can result in both a victory (with that one Mythos card that closes a gate+Akachi in a 1 player game, But not sure if that's 100% correct), and defeat (Innsmouth Devil Reef opening then surging, awakening Azathoth...).

If the Akachi one isn't legal as I wrote it, then shortest "victory" is 1 turn, even before you draw your second Mythos.

Which Mythos card are you referring to? I know you can close a gate with "Mysterious Lights Fade" but that requires everyone spending 5 clue tokens to do so. So winning on turn 0 with that card would not be possible since you don't keep the trophy and Akachi only has 1 clue token at the start of game.

Yes... Another way of having near infinite length games is exploiting the remove doom token locations... This can be done very easily with a large enough team. I would advise not trying this unless you really enjoy being bored.

Veet said:

Besides, you cannot do so if there is only one open gate in Arkham

I'm not sure infinite is the answer. I agree that it's possible to keep the doom track frozen and for the players, if they wish, to potentially stall the game for a long time, but what happens when you run out of mythos cards?

Also, Atlach would eventually get you through having no more gates left to put into play, so he's out.

Tobec said:

The Mythos card "The story continues" instructs you to reshuffle the deck, so there is an infinite loop.

And trophies can be spent :-)

Julia said:

Yep. Pretty much the only reason I'll say the game won't last for infinity, is because there is an infinitesimal chance of getting horrible die rolls (like 200 failures in a row).

Use the Inner Sanctum encounter from Dunwich to take every nasty mythos card out of the deck (should only take a few hundred turns) and most of the nice ones too, seal the two or three locations that the remaining cards refer to, close the remaining gates (turn in trophies to stop an immediate closing win), and then clean up the remaining monsters.

No gates in town, fewer than six seals, no more gates will open so no more can be closed, and no more doom or terror increases can happen (have Happy Days as the only remaining environment just to be sure) - stalemate.

Then spend as long as you like actually having encounters (ideally, your two remaining mythos cards should be Happy Days as a permanent environment, and Intermission - because that then does absolutely nothing).

(If you use the Woods, Black Cave, or Unvisited Isle to have encounters, eventually you'll run the corruption deck out if Black Goat is in, there's a CotDP South Church encounter that might eventually raise too much doom if nothing's done about it, and there's an inner sanctum encounters that can add new seals to get an eventual win)

cim said:

That infinite time strategy will only work without Innsmouth. With Innsmouth, you might wake up the ancient one accidentally by screwing up and running out of clues ;') with Kingsport, you just have to make sure that the mythos cards you leave in only bump half the rift tracks. Still, clever. I'll try it soon and let you know how it works after infinity.

That's why I picked "Intermission" as the remaining mythos card - all it does is raise the terror level by two, which Happy Days blocks. No movement (so no Kingsport rifts) and no bouncing off a seal (so no Innsmouth uprising).

Certainly getting that far would be much harder with Innsmouth in play, though.

(Question: what happens if the only Mythos card left is the shuffling card? Answer: the investigators are trapped in an infinite time loop and lose the game)

Julia said:

I thought it was you Julia. I'll look up the session report you refer to. I'm guessing Atlach is a GOO from one of the expansions? I'm slowly working my way through them so far.

Still I'm reassurred that the games usually don't run for that many turns!

The rule is, if an investigator is stuck in an infinite loop, the investigator goes insane and the loop ends.

An infinite game of AH would not be a loop though, since it would not be the same exact conditions stopping play. By definition, the game can't go infinitely, but any game can be arbitrarily long depending on circumstances. So there's no real answer to OP's question

As for shortest, yeah: opening mythos card could awaken Azathoth, or you could be playing a 1p game with Akachi and the first mythos card opens a gate and then closes it (there's one like this in Dunwich Horror).

But both games would not be very fun, and why would you play a 1p game with Akachi using Dunwich Horror?

cim said:

Ahhh, very nice ;'D theory slays the devil of practice yet again!

Tibs said:

I disagree. In an infinite game of Arkham the players go insane and must commit suicide to escape. But there is no escape.

Well, Tibs, it CAN go infinitely. You can take away all the fail-safes that the game has to ensure that it doesn't last too long (Doom removal at the church, Cim's "Duniwch Mythos" removal, coupled with passing that Rumor Mission), and keep the normal elements in check (Ashcan Pete with several choice tomes/spells to keep the gates, monsters, and doom tokens under control).

And Nameless DID ask for the "maximimal set of circumstances." So, if you look at it mathematically, it can, in fact, last infinitely. There's a small chance that the stars will line up right, but there are MANY elements that can allow you to give you an infinitely-long game (either on purpose or "by accident"). I don't want to try it, because, well, I'm not here to prove it can happen in real life. I think we can prove it in the math!

Nameless1 said:

Game length depends heavily on the number of investigators you play with. When playing with 5 investigators, my game last usually 14-15 Mythos. Something less (about 11 Mythos) when playing with six.

And yes, you're right, Atlach-Nacha is from Kingsport, and after his arrival, Arkham has never been the same again ::laughter::

Anyway, you can read my memories of the struggle against Eihort here !

EcnoTheNeato said:

I can prove it mathematically. Any given condition or set of conditions has a less-than-one chance of occurring. So any combination of conditions to allow the game to go one more round is less than one, say, P.

For the game to be stymied for N rounds will require a P^N probability. But since P is less than one and N is a positive integer, then P^N converges to zero as N goes to infinity.

It's essentially a more convoluted form of the question, "can you flip a coin infinity times and never get tails?" The answer to that is also "no."

Tibs said:

Ah, but that's assuming that after a certain number of coin flips the order of the universe does not shatter and all laws of physics become undone. I mean, really, have we ever tested what the results of even 100 billion consecutive coin flips to heads would be? I think not. We simply presume that it would be the same as a lesser quantity, lacking evidence to the contrary. But I say that 100 billion consecutive coin flips will bring upon us all unspeakable doom. Unspeakable DOOOOOOOOM!

*breathes in*

DOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMMMMMMMMMMMMM!

Avi_dreader said:

I have a friend who likes to write computer programs to test this.

PS-Tibs, I think that's assuming one uses dice to figure the outcome. I think, between the Kingsport skills, one need not need to roll dice at all to create an endless scenario

Tibs said:

That's only true if P is less than one for any N. I think it's possible given sufficient time and initial luck (and certain expansion elements) to set up a situation such that once you've got into that situation, P is exactly 1: there are no non-deterministic ways of ending the game which cannot deterministically be countered by other effects or prevented from triggering. "