Custom components can be found here:
Expanded Investigator Pool: Leo Anderson, Agnes Baker
Ancient One: Yog-Sothoth
Required Investigators: Agnes Baker, Sister Mary
The Dunwich Horror begins the game on The Black Cave. It has +1 toughness, an awareness of -1, and in addition to its special movement, it moves like a fast stalker monster on white every mythos phase. It can never be moved from the board or relocated in any way, except by defeating it in combat (which returns it to The Black Cave). Instead of the usual reward for defeating it, an investigator defeating it clears the Dunwich Horror track, draws from the top five cards of the unique item deck, keeps one, and discards the rest. For each token on the Dunwich Horror track the Dunwich Horror gains an additional +1 toughness. Once per game, defeating it also removes one doom token from the doom track.
Investigators moving through a street adjacent to The Dunwich Horror must roll a die, and on a 1-3 draw a madness, injury, or reduce maximum sanity or stamina by one (though never to zero). Investigators with madness or injuries can not retire.
When the doom track reaches three, place one random monster on each unstable location in Dunwich. Blue bordered and yellow bordered monsters in Dunwich move like black bordered monsters instead.
When the doom track reaches seven, The Dunwich Horror adds a doom token on rolls of 2-6 instead.
If Yog-Sothoth awakens, he has 5 extra doom tokens and physical resistance.