'Arkham Underground' board/expansion

By thecorinthian, in Fan Creations

we could just use the bgotw cult encounter cards?

Plenty of good suggestions.

How about we make a list for the various official G.O.O.s that are known to inhabit the depths of the earth?

It seems like nearly half of them do, and we might be able to fuse the underworld to some of them somehow.

Cultists activity seems to be a no brainer. The perfect spot for some nerfarious summoning is in an underground coven. With regards to cutlists there are any number of rituals they might be at work on. Summoning the Great Old One need not be the only one. Earthquakes. Floods. Infernos. Plauges of insects, rats, carrion. Hordes of undead. Gate activation.

A "super monster" or minor great one that is being summoned underground seems entirely reasonable.

Perhaps, there is an underground unstable location that triggers a specific super gate. The super gate can have a variety of effects, and be extremely difficult to close, but crucial that it is done.

I like a deck that would be used for lost investigators.

Frank's Outer World cards seem like an entirely good idea.

Thecorinthians first post and possible underground locations are solid. I would rather like to see a location under the graveyards, the woods, and along the docks.

If there was someway to tie this into the vast tunnel network under Innsmouth and Kingsport we would be really onto something.

* Rescuing People. Each time the Blights come in, Investigators have the chance to crawl into the pit to rescue them. Since Blights are really bad, springing prisoners is its own reward. But by itself that's a painful unfunded mandate, so you should get something for succeeding in springing prisoners.

I like this suggestion, and we could come up with numerous reasons for who is kidnapping, enslaving and worse.

In my own expansion I had a triggering mechanism, in which ghouls would ambush investigators in the streets, and if they didn't evade/fight the ghouls the unlucky investigators were dragged down to the ghoul feeding pits.


* Canvassing Ghouls. As the Ghouls defecting to the dark side provides a penalty and ghouls supporting the Investigators provides a bonus, each vascilating Ghoul provides a good distraction.

I don't know enough about this war between ghouls to comment. It doesn't mix with my general take on ghouls, but that doesn't mean it might not be extremely colorful to have dark-side politics.


* Bubbling up monsters from the pit. The key is that the extra monsters spawned from the pit will eventually move into Arkham and count against the monster limit in town. If they come and move in waves, going down and using the banishment circle in the pit or fighting the monsters in the hole can prevent a cascade of Terror level rises. Especially if Terror rises cause people to get kdnapped, that could be a death spiral that would demand Investigator attention.

I rather like that if one goes done far enough one can enter the Abyss. A gateway to the Abyss would not be unreasonable. Over all a flood of horrors moving upwards that wishes to drag the citizens down is brilliant.


* Possibly Rifts. The Rift mechanic is extremely brilliant, because it demands an equal amount of attention no matter how diluted the game gets, because it triggers off of regular movement icons that appear on mythos cards in every set.

Perhaps, a variety of the Rift mechanic. Something is building up slowly, and if the investigators don't go underground and defuse it something really nasty will be released like a vast worm that shall rumble Arkham to ruins.

* I don't know enough about this war between ghouls to comment. It doesn't mix with my general take on ghouls, but that doesn't mean it might not be extremely colorful to have dark-side politics.

The Ghouls of HPL are pretty weird. Some of them are just humans who, when exposed to dark knowledge, become meeping flesh eaters. But frankly, being a meeping flesh eater doesn't seem to be that bad. Richard Upton Pickman, the ally you can get from the Graveyard, is a Ghoul. A ghoul who happens to be on humanity's side because he used to be a human but found that he mostly preferred the company of ghouls. The one we get as an ally is the ghoul ally from The Dream Quest of Unknown Kaddath, not the murderous painter from Pickman's Model (though the two characters have the same name).

-Frank

Frank said:

The one we get as an ally is the ghoul ally from The Dream Quest of Unknown Kaddath, not the murderous painter from Pickman's Model (though the two characters have the same name).

Sorry, but... how do you know that?

The two characters have the same name because they're meant to be the same person, before and after he comes a ghoul. The personality may be different in Dream-Quest because a) he's become a ghoul, and b) it's a dream.

Anyway.... Ancient Ones that live underground, but which haven't been used yet: when I was worked on my Burrowers Beneath ideas, I wasn't going to make any new AOs, just a bunch of those 'supermonster' heralds. Most of the good AO concepts that haven't been used are from Ramsey Campbell and Clark Ashton Smith, which creates a bit of a problem in the latter case because they often live on other planets. Some of the creatures I was going to use are now Innsmouth AOs, but the others were going to be:

'The Green God' , also known as 'The Horror Under Warrendown', from... The Horror Under Warrendown. A giant head made entirely out of vines, worshipped by rabbity cultists. It's a sort of perverted harvest god. Its worshippers offer people poisoned fruit which turns them into rabbit mutants. My idea was that in order to attack the Green God, you had to draw thing called a 'Harvest Taint' card, and some of them were fatal or just very nasty. As I understand it, the Innsmouth Look now does something quite similar.

The Worm That Gnaws In The Night - a gigantic worm that eats away at a planet's insides. (A cult needs to somehow summon it to Earth from Shaggai.)

The Dweller In The Gulf - a huge carnivorous tortoise-monster that has survived in the watery caverns underneath Mars for millions of years. Same idea as with the Worm That Gnaws; the cult has arranged for the Dweller to come to Earth somehow. The Dweller has an aura of sleep which is obviously a good basis for an in-game effect. Also, it eats your eyes.

Mordiggian - the 'Charnel God', a big shapeless black smoke-monster who is worshipped by Ghouls in underground crypts.

Geol - an earth god from Clark Ashton Smith stories (apparently). I can't find any information about him, so he probably only gets a passing mention, but that leaves us with a blank slate if we want to make up a giant cavern-dwelling earth-god.

Rilm Shakorth (I think that's right) - the 'White Worm' from The Coming of the White Worm. A huge ice-worm that freezes people solid.

Ubbo-Sathla - a giant protoplasmic amoeba that lives on the ocean floor (I think, can't remember exactly). It constantly spawns sloppy nasty blobby offspring.

Vulthoom - an alien plant that lives underneath Mars. An immensely intelligent god from another dimension. Someone made an AO of this a while ago, I think. Anyway it's not a particularly good concept for an Arkham threat, since it's a bit too outer-spacey, but it does live in underground caverns.

why not introduce a new mechanic rather than just making a bad ass monster appear ala dunwich horror. What if the investigators could somehow fight the herald to make things easier for them finishing the game. You could give the herald a special attacka and combat modifiers, but not so strong as an AO. Maybe make a couple missions they have to do before they can reach the herald to battle it.

just think of it as the herald is a monster too, fighting herald per say doesnt fit the rules, why not just have a monster!

ivory_tower said:

wWhat if the investigators could somehow fight the herald to make things easier for them finishing the game. You could give the herald a special attacka and combat modifiers, but not so strong as an AO.

This is almost exactly what I was going for with the 'supermonster' idea. The only reason it's a monster at all is so that there's something on the board whcih players can go and attack in order to hurt the herald. The herald then has 'hit points' just like an AO. The reason for doing it this way is because you can't really have a special 'battle' phase in the middle of the game.

The herald could have a doom track of its own, and there are a few ways that could work, but mostly it might create more problems that it would solve.

when do you want to start making me board? just wondering.

Right!

Since no-one else has taken the initiative yet, here's a very rough 'first draft' of the board.

Most of this was made up without a specific idea of what should happen at each place.

3628889879_23a2e780f0_b.jpg

Full size version here: farm4.static.flickr.com/3542/3628889879_23a2e780f0_b.jpg

NOTES:

- The background image is a D&D dungeon map I found on DeviantArt and cleaned up a bit. If anyone has a better idea, say so. I will lower the contrast for any later version, so it fades into the background more.

- There are only two neighbourhoods. I figure that there's no sense adding more unless we have a lot of good concepts for locations/encounters. The ones I have so far are:

- Labyrinth - most likely rewards: spells and sanity. Most likely problems: monsters and delays.

- Dark Temple - very very odd stuff, a bit like the Inner Sanctum but probably even more evil. Game-changingly good rewards, in exchange for your soul etc.

- Crypts - Pretty 'miscellaneous' encounters - plenty of clues to find, but also blessings and curses. Any better ideas for how the way back to Arkham should work?

- The Pit - the 'special' location. Not sure what should happen here yet. Its own special encounter deck, maybe? This is where the supermonsters could appear.

- Vaults - not sure what the 'theme' of vault encounters should be yet.

- Rare Book Room - secret access to the 'special books' that Miskatonic U. keeps locked up. I basically had the idea that there'd be a lot of encounters whcih were one-off chances to resolve particular tomes - so there'd be an 'Eltdown Shards' encounter, a 'Livre d'Ivon' encounter, etc, and lots of others we'd make up. Plus, there'd be encounters that would find you random Tomes, and help you read Tomes you already have. Since there'd be a bias towards Lore checks on tome-related encounters, we throw in the occasional Luck-check-based encounter whcih completely screws you over if you fail it.

- Storm Drain - monsters, and hidden stashes of contraband and stolen goods and that type of thing. Any better ideas for how the way back to Arkham should work?

Even with all of those, there's still room on the board for another location or two, OR a special track of some kind.

Also, while browing deviantart, I found this: graysapphire.deviantart.com/art/Sewer-Beast-19638447 . Isn't that great? We clearly need to use that as a sewer-based AO, or something.

Hey, that is looking really good for a first draft. I like the map image and by coincedence, I also found that same creature image and made a monster for it.

i was thinking of the Black Lake that is in The Festival, could be used as a possible escape route!

you also need a under the graveyard location!! i like your board. what kind of "clock" are you thinking? more locations: the poral staircase, the hidden shafts ( like in the case of charles dexter ward where he keeps those monsters underground), a ghoul hangout, how about finding a tower that feel into the earth 3 thousand years ago, you could find crazy good items there.

sea of maggots? are you going to have outerworlds? cant wait to see what you do with it, and love the earthy background to the board!

pittplayer said:

are you going to have outerworlds? cant wait to see what you do with it, and love the earthy background to the board!

I wasn't going to put new OWs on it, since I think that any new OWs that are designed at this point just end up diluting the deck and increasing the number of 'Other' encounters that will be drawn.

However... this is meant to be a group effort, so if anyone feels like designing new OWs, go for it. One way of solving the OW dilution problem would be to introduce a new colour. For example, there could be a blue-orange OW and a green-orange OW. That way, at least you'd only be diluting blue and green a bit.

thats cool no need for outerworlds, innsmouth kind of incorperates a outerworld into a location ( you know the one after devils reef) maybe we could do that with this board.

pittplayer said:

innsmouth kind of incorperates a outerworld into a location ( you know the one after devils reef)

(I don't know, because my copy of Innsmouth hasn't arrived yet! I guess you're talking about Yhanthlei, but I don't know how it works. Anyway, I'm sure I'll find out soon enough).

Including OW-style content and encounters in Arkham locations is a good way of doing it. All that's really needed is a reason for investigators to go to particular locations and have encounters there. The obvious answer is some sort of 'timing track', like the rift tracks or the dunwich horror tracks or the deep one rising track.

OK this has reminded me of the idea I had for my Burrowers Beneath board. I never worked out all the details, but here's how it worked:

Somewhere on the board (maybe around the edges, or maybe at one end, or surrounding The Pit) there's a sort of web of monster movement tracks with litle 'stopping points' on them. The investigators can't move along these tracks, but there are little 'tremor markers' which can. Each Mythos phase, the monster movement pattern determines where you place new Tremor markers, and which ones move. They gradually get nearer to actual locations and street areas, but their movement isn't completely predictable, so the investigators can see when things are likely to start appearing, but can't be precise about it.

The 'tremor markers' are actually what you might call 'blips', i.e. they have different things on the backs of them. When they reach locations or streets, they turn into whatever the thing shown is. So some of them turn into random monsters (because the tremor was the sound of a tunnelling monster), a few turn into specific monsters (Cthonians would be pretty common, for example), and others are one-off events (earthquakes, so everyone loses 1 Stamina, or everyone is delayed , that type of thing). Obviously any monsters spawned would start moving around as normal.

The only missing thing there is how you do something about it. Part of my idea for a 'scientific item' deck was that it would include things like Seismometers, whcih would let you look at some of the markers and discard the ones you didn't like. However there would also be quite a few encounters on the underground board locations which let you mess around with the tremor tracks.

Tremors wouldn't necessarily need tracks of their own. They could just be 'hidden' or 'face-down' monster markers, which move around the underground board until somebody kills them. They rely on being 'face-down', though (so that you can't see what they do until you fight them), which is a bit fiddly for monster markers.

The first time I tried this idea, I ended up thinking there was no need to add a new board, and all the ideas could be done with a herald which caused tremors to appear on the main board.

The alternative is a simpler 'tremor track' which just accumulates tokens until there's a big disaster of some sort. But if that's what we're going to do, I think the way you get rid of the tokens should be done in the actual encounters on the board , so you have to go and have encounters at the underground locations until you find one that gets rid of a token. Obviously there'd have to be a lot of those encounters which helped with the track, but that's ok because we don't have ideas for most of the locations yet anyway.

It's also a good opportunity for a sort of 'story' for the board - there are four importants seals or artefacts or altars or whatever, and you have to go and deal with them in order to stop the tremors. So for instance:

Dark Temple - there's a blasphemous altar you can find. Some of the encounters let you smash it, other encounters let you sacrifice an Ally on it, and so on. Usually, you get the choice of rewards: items/clues, or removing a token from the tremor track (or whatever it's called).

Vaults - there are occult seals which strengthen the walls, and you can repair them using certain items, or replace them by spending clue tokens.

Storm Drain - the Sheldon Gang have nicked a bunch of Cthonian eggs and the Cthonians are angry. Getting the eggs back involves finding the gang's stash, which means having encounters at the Storm Drain until you get lucky. A few encounters would get you what you're after, but some of them would be riskier or more expensive than others.

Rare Book Room - a particular spell can help you, or... something.

Obviously these ideas need work.

tremors plague arkham and then a huge grave worm appears!!! i am all in on the superbeast idea!

Another thought:

Instead of making the Dark Temple an 'Inner Sanctum' type thing, I'll make it into a seperate location, the only 'unstable' location in the Underground board. The Labyrinth will require you to end your movement, and you can only get to the Temple through the Labyrinth. So it's a bit of a pain to get to the Temple, but not that bad.

There won't be any Mythos cards which open gates at Dark Temple, but there will be plenty of encounters which open gates, so if you sit there having encounters (which you'll need to do) there's a chance a gate will open first, and you'll have to get rid of the gate before you can keep doing the stuff. Does that sound ok? Or is it a bit crazy to only have one unstable location on a board?

Also, I'll rename the Dark Temple as ''Festival Cave' or something of the sort, and make it obvious that it's the actual cavern from The Festival.

crazy? no, all boards should have unique things about them! how bout this for a location? Black Lake: Movement: you may take a lose one sanity and end your movement at the river docks. or Sunken Crypt: Upkeep: if an investigator starts their turn here they lose two stamina unless they discard a ally card.

sorry for typos in above post! anyway how about at the end of the tunnels you find a sunken and toppled dark tower under the earth that used to be lived in by a evil sorceror thousands of years ago? that could be your dark temple!

As I said on the Pickman's Model thread, locations where you have to stop before moving on are really annoying and break the flow of the game. Even if having one investigator slog through and then slog back is worthwhile in terms of total turns spent to total benefits gained, it's still drawing a character out of the game where they don't interact with the rest of the team. I don't like it.

A better mechanic is to have the downstream locations begin the game closed, and then have in-game events remove the closed token. That way one investigator can go and discover the way to the labirynth and then have another investigator actually do whatever needs to be done there. This emphasizes the "teamwork" aspects that make cooperative board games fun and interesting. Whenever possible, pains should be taken to make the different investigators more connected and not less.

-Frank

Hello lads,

I am in synch with Frank that the more design features that allow investigators to cooperate the better the game tends to be. That being said, I am not opposed to a player that wants to go solo, or if the game play gets so desperate that investigators might take on heroic roles. So both routes seems viable.

Thecorinthian your rough map outline is a good start, but it seems to small in scope. Like Pittplayer I would like some connections with the graveyards, and tunnels that reflect the necromancer lair in Charles Dextar Ward (a necromancer that might come into play an give order to the undead might be grand fun). Tunnels could also lead to the bank as you suggested, the church, maybe the Magic Shop, and certainly the Inner Sanctum. As silly as this might seem I see a vague inverted pentagram lay out. Read on and you'll see why.

Your 'blip' idea is fantastic and I came up with a tentative idea how this might work, although explaining it might be a chore. Even, if my idea gets a frown, the blip needs to be hammered into regal game perfection.

The basic idea is that there are four upward blip corridors that investigators can not enter. Each corridor has three sections, which represents a movement upward. Each corridor is linked to the movement symbols on a Mythos card, just like in Kingsport. The blips aren't known until they reach section three, and then they are revealed. The four corridors relates to a section on the underground, and a generalized section of surface Arkham.

Some of the blips are undead/ghouls, some are worms/Chthonian, some are deadly tremors and some are the tenacles/limbs of the nearing super beast. (It need not be limited to this.)

The tremors and the tenacles I'd like to go into a little greater detail with.

Tremors are bad news. They are also the rarest of the blips. If a tremor reaches the surface a neighborhood in Arkham is barred to the investigators, and all its locations are reduced to rumble. Any investigators in these locations are devoured. The Terror Level goes up 1 or 2. Furthermore, the corridor that the tremor emerged from is closed. Any blips in the corridor shift randomly to new corridors. If every all four corridors are closed, Arkham's foundations are removed and Arkham crumbles into an open grave. Game Over!

The Tenacles burst through the streets of Arkham in a massive whipping forest of maws, tongues and limbs. Any investigator in the current street location is dragged under to some as yet undecided location. A tenacle monster marker is placed on the board. (I envision that it would be quite tough, and they may vary). The Terror Level increases 1. Now, when every an investigator enters a street location with a tenacle monster they must evade, or they will be drawn into one round of combat. If the investigator doesn't defeat the tenacle in one round the investigator is dragged underground.

If there are ever three tenacles adjacent to each other then the middle tenacles position represents the street and neighborhood that is pulled under Arkham. Terror Level jumps by 3. That neighborhood region is effectively a black hole for the rest of the game. Mythos cards and gates would be taken into account and altered accordingly.

Your archaeologist dig site would play a big part. The archaeologists will have discovered that far beneath Arkham there are four mysterious large ancient monuments that seem to correspond with the four foundational corners of Arkham. Somehow these relics can be reactivated one by one. (There is an order to this, and it is moderately hard to do.) Each one represents a certain blip type, and once activated that corridor has a ward against one type of blip. If every all four are reactivated at the same time then all the corridors are warded from all blips, for the remainder of the game.

The only problem is a super beast will strive to destory any that have been reactivated.

Not to mention that getting to each underground monument location isn't a walk in the park, with plenty of opportunities for ambushes from ghouls, vampires, gnawing worms and blood cultists. And that the archaelogical site (also a healing point) is in jeopardy of being overrun, and with it the deceiphering of the monuments and their activation methods.

I 'd say there are some good reasons for the investigators to venture underground.

Anyway, that is that for the moment.

Blip Tokens could be placed in underground locations almost every turn by the Rift Progress mechanic. Each of six locations correspond to each of the six basic movement types. Once in the underground area, a blip counter has a movement icon. My suggestion would be that they each be Slash, Triangle, Star, or Hexagon. The movement tracks down below eventually spill out to the equivalent of vortices, save tht each vortex is different and represents a different part of town or the outskirts.

A Blip token is revealed when an Investigator enters their location, or when they go to the surface. Once that happens, they do something based on how they are revealed:

  • Monster: Once revealed, a monster is just a token on the board. The monsters should mostly be Cthonians, Ghouls, Vampires, and Cultits.
  • Kidnappers: If the Kidnappers are revealed upon reaching the surface, they kidnap someone and you draw a blight card. Eventually you can rescue them. If they are revealed underground, you can have a cult encounter to disburse them.
  • Tremors: Rubble or an undergorund encounter depending upon where it is revealed.
  • Empty: Once revealed, nothing happens.

-Frank

Re: stable/unstable locations, and Frank's point about 'end your movement' locations: Frank, you're right, 'End-your-Movement' places are a bit crap. So we make up a new colour of 'stability' - so as well as green (stable) and red (unstable), there's yellow (collapsed).

Yellow locations have 'cave-in' markers placed on them at the start of the game, or we could just use 'closed' markers for convenience. It's not like there's no precedent for this: unstable locations have clue tokens placed on them at the start of the game, which is essentially the same type of game mechanic. Cave-in markers prevent the investigators entering the location. (We're treading on the toes of Shudde-M'ell's rubble markers a bit, but he's only one AO, so I don't mind so much).

The underground board's encounter decks all have specific encounters which open up specific other locations. So if you want to remove the 'cave-in' marker from the Dark Temple, you've got to go to the Labyrinth in order to find an encounter which lets you discover the dark temple entrance.

On terms of teamwork, I already had the idea that there would be quite a few encounters which affect all investigators in the same location, or which gave you a specific advantage if there was another investigator in the same space. So for example, navigating the Labyrinth is easier with multiple people, and you've have encounters like this:

"You attempt to navigate the maze by marking the archways with chalk if they lead to a dead end. Make a Lore (-3) check, but gain (+1) for each other investigator in this location. If you pass the check, gain 1 Clue token, or remove a Cave-In marker from Dark Temple or the Crypts."

Obviously, if we're doing it like this, we suddenly have an excuse for just adding new locations - because you really need to use them to open up the board. So now I agree with Lemmingsunday's point about the board not being big enough. It needs to have another neighbourhood, and the neighbourhoods need to have slightly unconventional layouts, because you're really going to have to explore the place. I'll start tinkering with the map again.

I think we've found one of our core aims for this whole board: ' explore using encounters '. I don't know about you guys, but in my experience, Arkham Encounters are often just the 'side effect' of going where you want to go in Arkham. So for example, quite often you go to pick up a clue, or to remove a Rift token, and you just hope that the encounter at the location doesn't screw you over too badly. This is not how the underground board should work. There needs to be a specific reason to visit every location. It doesn't have to be game-changing, but even the 'spare' locations (whihc don't affect the tremor tracks or whatever) should achieve their goals through random encounters. For example: there's no hospital on the underground board, but one location is weighted heavily in favour of encounters that restore sanity and stamina - although there's a variety of odd side-effects too. There's no shop, but you can rummage through items in the vaults, and usually it'll give you a shop-like effect in the encounter - "Draw a common, a unique and a spell, and purchase one of them" etc. There are places where you can spend trophies, but you don't know what your options will be until you draw the encounter, and it might take you a turn or two to find something you really want. Of course, the 'prices' will have to be quite favourable in order to make up for the time-wasting that might be required.

The expansion doesn't need new Scientific items or any of that rubbish, because all the cool effects which you could put on items can probably be put on encounters instead. Pittplayer - your 'Black Lake' and 'Sunken Crypt' ideas are not bad, but really they're 'fixed' encounters and they would force people to try to avoid stopping there. There's nothing wrong with making locations that people dread to visit , but it should be done by making a consistently threatening set of encounters for that location, not by putting an encounter-like special ability on the location itself.

Re: blips and monsters. If this is going to involve special tracks on the board rather than just using normal monster movement paths, then it becomes a lot easier because you have to put an explanation in a rulebook anyway, and suddenly it's not all going to have to fit on a herald. What we seem to be talking about is a 'tremor cup' which contains random tremor markers. Specific heralds/AOs could 'add' their own unique tremors to the cup, so it customizes a bit depending on who you're up against. In fact, that should probably be the main 'worshippers' ability on subterranean AOs - although the supermonsters themselves will need to be heralds rather than AOs, so it may just have to be one of a few abilities.

However, having a 'tremor cup' and an 'underground monster cup' is very clumsy. Seperating out the monster cup is always a pain with Black Goat. I think most of the tremors should produce random monsters, with only a few specified Cthonians/Ghouls/whatevers. That way, we can justify making the players rummage through the main monster cup for the specific monsters (because they won't have to do it very often).

The blip rules you need aren't much more than this:

- Whenever the monster movement pattern on a Mythos card matches one of the patterns at the end of a tremor track, draw and place a tremor marker on that symbol. Place it face-down without looking at it.

- Tremor markers each have a monster movement symbol on one side. Their movement is triggered by monster movement patterns in the Mythos phase, just like monsters . They could even have black or red boarders, to indicate 'normal' and 'fast', although this subdivides them and makes it easier to 'card-count' to work out what they are.

- "Whenever a Tremor marker moves into the same street or location as an investigator, or vice-versa , flip the tremor marker over and follow the instructions on it". We get into difficulties with this part, because the tremor markers can't be very big (I imagine medium-sized circular things) so there's not a lot of space on the back of them. Do we want each marker to actually explain what happens , or do we want a set of symbols or numbers which.... oh god, I'm such an idiot! HERE is how we do it: tremor markers are double-sided! They have monster movement symbols on both sides, and it doesn't matter which way you initially put it down, as long as you don't look at the other side. So when it 'encounters' someone, you flip it over and look at the symbol that's been hidden, and that symbol determines what happens according to a chart in the rulebook. There's no reason why some of the symbols can't cause events in Arkham itself, as well as in the underground.

- There are a couple of long tremor tracks which lead to 'The Pit'. If a tremor marker falls into the Pit, it adds a Doom token. However this is unlikely, since tremors are probably going to move out into streets/locations first. If the players see a marker heading for the Pit, it's in their interests to head for nearby locations and hope to have encounters which remove or move the marker.

Re: travelling to and from Arkham: We still need a way of doing this. Putting special abilities on particular locations is quite clumsy, and since those abilities only worked for people in those locations, we can't add abilities to Arkham locations that way, so it helps get back but it doesn't help you get into the underground in the first place. I really don't want to have to design a little token that gets put on an Arkham location in order to indicate that it's got a cave entrance there or whatever. That's really fiddly, and I hate the 'aquatic' markers. We could make travel dependent solely on encounters, so we design a bunch of new encounters for the Black Cave, the Graveyard, South Church etc. etc. and you just have to go and have encounters there until you get one that takes you through. That would be in keeping with the 'explore using encounters' theme of the expansion.

Or you could add "To the Church", "To the graveyard" etc to your map