I had a bunch of my Arkham Horror stuff spread over the dining table (my gaming platform of choice) last night and had to clean things up for some company we had coming over that evening. I had sorted out the Spell cards by the basic game and expansions to adjust Spell appearance, frequency, or probability.

Somewhere in there, I got this idea to modify my Mythos deck for the exact same purpose. Now, I like the idea of Environment cards and Rumors, but I’m of the opinion that they’re poorly handled. They cause more of a distraction to gameplay itself than they provide additional challenge to investigators. So I removed them. All of them.

Next, because I tend not to make much use of the expansion boards at the current time (and I haven’t rewritten their location encounters yet), I removed every card that opened a gate or spawned a Clue token, or even had an effect that could occur exclusively on one of these expansion boards. That pared the cards down quite a bit.

Next, I took out cards that referred to removing any monsters from the board I was no longer using, like Cthonians, Elder Things, Byakhees, or whatever, leaving one card that refers to Rat-Things because I’m, A) thinking of putting them back in, and B) the card also mentions Witches and Warlocks, which I do still have in the mix.

Each of the “minor” Unstable locations have 2 gate openings (8 cards), while the “medium” Unstable locations have 4 gate openings (12 cards) including one gate burst, and the “major” Unstable locations have 7 gate openings (28 cards) including one gate burst. I’m also using Lurker’s dual-gate cards (4 cards).

The probability of a gate opening at one of the major locations (on the first turn) is thirteen per cent. That probability changes as cards are taken out of the Mythos deck, and whether the location has been sealed or not (with one gate burst being in there for good measure). A “medium” location has a six per cent probability of opening.

You could look at the Ancient One’s main “schtick” as trying to open one of the major locations as soon as possible, and then pouring monsters into Arkham to overrun the place. Reaching the gate limit is more difficult than reaching the monster limit, and I think maxing out the doom track falls somewhere between the two.

My next step will probably be to replace a lot of the Arkham gate-location Mythos cards with the “either-or” cards from the Miskatonic Horror expansion. That way, we can choose to play with the expansion boards, or not. The major deciding factor will of course be how many of them are Environment cards.

What follows are the Mythos cards I kept in the deck, which total sixty-six.

Arkham Horror (24 cards)

Add Two Monsters to the Board:
Horror at Groundbreaking!
Lodge Member Held for Questioning!
Picnickers Panic!
Sheldon Gang Turns to Police for Aid!
Slum Murders Continue!
Southside Strangler Suspected!
Terror at the Train Station!
Witch Burning Anniversary!

Remove Monsters from the Board:
Campus Security Increased!
Church Group Reclaims Southside!
* Feds Raid Arkham! (all street areas)
Gangs Clean Up Easttown!
Lodge Members Watch the Night!
* Manhunt in Arkham! (all location areas)
Merchants March on Crime!
Police Step Up Patrols in Northside!
Rivertown Residents Take Back Streets!
Vigilante Guards the Night!

Blue Flu!
City Gripped by Blackouts!
Family Found Butchered!
Missing People Return!
The Story Continues…
Strange Power Flux Plagues City!

Curse of the Dark Pharaoh (8 cards)

Bank Foreclosure
Corpses Preserved
Escape from Arkham Asylum!
King of Cards Cancels Show
Murderer at Large; Victims’ Brains Missing (two doom tokens)
Murder in the Museum (two doom tokens)
Museum Artifacts Stolen
Museum Haunted

Dunwich Horror (2 cards)

Black Sabbath! (GB – Woods)
Strange Waves Subside! (GB – The Unnameable)

Kingsport Horror (1 card)

Wild Visions Plague City!

The Black Goat of the Woods (10 cards)

Charity Auction!
Checkered Cab Trials Begin!
Construction Crew Conundrum!
Lightning Strikes Twice!
Mysterious Crates Found Empty!
Pets and Wildlife Mutilated! (GB – Black Cave)
Rash of Missing Persons!
Strange Whispers Promise Vengeance!
Tongue-Tied Teacher Taunted!
Vivisection Victim! (GB – Witch House)

The King in Yellow (9 cards)

x6 The Next Act Begins!
Police Proclaim Cult Crackdown
Uptown Hosts Famous Publisher

The Lurker at the Threshold (8 cards)

Citizens Urged to Lock Doors (GB – Graveyard)
Double the Trouble
Eerie Coincidences
The Evil is Everywhere
Mysterious Lights Fade! (GB – Independence Square)
Noted Author Dies
Strange Woman Distributing Words (GB – Unvisited Isle)
Surrounded by Mystery

Various (4 cards)

x4 Strange Sightings! (I used the four from Miskatonic Horror)