A few couple of past days I was thinking of Arkham Horror game mode, which not involved other world traves so actively and does not makes em the center of the game itself. And here what I came to:
During the game setup, no clue tokens placed on the board and no ancient one is picked. Heralds, guardians and institutions are forbidden.
Clue tokens are now separated into two categories:
1) Investigation tokens. Those are placed on the board as an effect of Mythos card ONLY. Investigators no longer obtain them by just ending their movement in their location, now they need to successfully pass an Encounter at this location, and after passing it they may claim 1 Investigation token from their location. All investigators have shared Investigation tokens pool. This pool represent knowledge of the group about thing(s) they're facing.
2)Old clue tokens. Those coming as starting posession, or obtained DURING the encounters, or exchanged for monster/gate trophies at the representive location, etc, but NOT taken from the board.
Changed Mythos Effect:
Now, instead of opening the gate at the printed location, monster appears there and a Doom token added to the doom pool. If as a result of it, doom pool contains 3 doom tokens, remove them all and place a face down gate marker at the printed location, not spawning any monsters. This gate is unexposed. Placing a gate removes all investigation tokens from it's location.
Changed Gates:
Face down gate marker is unexposed. There is two ways it can be exposed:
1) Mythos card indicates it's location. In this way, gate marker turned face up, monster emerges from it and a an additional doom token is added.
2) An investigator successfully passes encounter in unexposed gate's location. In this way, gate marker is turned face up, but no monster emerge and no doom tokens.
Closing/Sealing Gates:
To perform an attempt of closing or sealing of gate, an investigator must be at the exposed gate's location during the Arkham Encounters phase and must discard 1 investigation token from the pool. Then, he draws a Other World encounter card, corresponding to gate he's located at. If he successful at this encounter, then he makes Fight/Lore check against his gate as usual. Gates are sealed by default rules of 5 clue tokens or Elder Sign item equivalents.
Gates Erupting:
If Mythos card indicates location of exposed gate, this gate erupts. Monster surge occurs at the adjacent street, gate marker is removed and doom token is placed at this location. It was overtaken by forces of mythos. Treat it as being closed.
Winning/Losing:
Here comes the tricky part.
Atm I consider winning the game by points.
For example, both sides(Investigators and Mythos) have 0/50 points at the beggining of the game.
How Mythos gains points:
Monster appears: +1
Investigator knocked unconscious/driven insane: +3
Gate opens: +5
Gate erupts: +10
If Mythos points reach 50/50 - Ancient One awakens. Draw an ancient one at random, fill his doom track entirely and commence the battle.
How investigators gaining points:
Monster defeated: +1 per monster toughness
Investigation token obtained: +1
Gate manually exposed: +2
Gate closed: +3
Personal Story Passed: +4
Gate sealed: +5(does not stacks with closing)
If Investigators reach 50/50, then investigators had driven away evil from Arkham. Happy end.
To ignite things up, maybe it worth to draw mythos card based on inv's numbers, for example:
1-2 players: 1 mythos card per turn
2-4 players: 2 mythos cards per turn
5-6 players: 3 mythos cards per turn
7-8 players: 4 mythos cards per turn
Jusr sharing my thoughts.
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