Here's my multi-faction yet still 100% Mi-Go deck.
Of course, in order to pull off a Yog/Shub deck that has only Mi-Go characters (the Doppelgangers just turn into more Mi-Gos), I had to dip into some CCG cards. But I think that's the fun part of playing with the old black-border stuff. With an expanded card pool you can pull off just about any theme you want and still make it viable.
I originally made this as an all Shub Mi-Go deck. Much to my surprise, it performed well when going up against my main opponent's Investigator decks and remained undefeated for a time. However, when pitted against my own decks - most of which are Mythos-based - it has since gone on a long losing streak. I realized it lacked ways to directly target opposing characters, had few surprise elements, and relied solely on the icon struggles to win. Not good. I'm hoping the inclusion of some better Events and the new Mi-Go Skull relic will help it out.
I've also considered adding 2 copies of Yog-Sothoth (perhaps In Whom The Spheres Meet?) and then sticking the Mi-Go Skull on him just for kicks. I'm not sure how well that would work out resourcing-wise, but it might give this deck a much needed boost in longer or multi-player games.
Here's my revised edition:
CHARACTERS: 27
x3 Harvesting Mi-Go
x3 Mi-Go Caretaker
x3 Ageless Mi-Go
x3 Mi-Go Guard
x3 Mi-Go Scout
x3 Mi-Go Observer
x3 Mi-Go Slave (CCG Yog Mi-Go)
x3 Child of the Kingdom (CCG Yog Mi-Go)
x3 Doppelganger
EVENTS: 12
x3 Balance of Thoth (CCG)
x3 Casting off the Skin
x3 A Single Glimpse
x3 Calling Down the Ancients
SUPPORT: 11
x2 Inter-dimensional Transporter
x3 Mi-Go Skull
x3 Mi-Go Scalpel
x3 Fungal Growth (CCG)
Total 50
CCG CARD SYNOPSIS
Mi-Go Slave
(Yog Character): 3 Cost, Mi-Go, CA Skill 3, Transient, Action: pay 1 to return Mi-Go Slave to your hand if it entered your discard pile this phase.
Child of the Kingdom (Yog Character): 3 Cost Steadfast 1 Shub, Mi-Go, CI Skill 3, Action: sacrifice a Mi-Go character to choose a character. That character gains TI until the end of the phase.
Balance of Thoth (Yog Event): 1 Cost, Spell, Action: remove a wound from a character. Then, place a success token at a story of your choice.
Fungal Growth (Yog Support): 1 Cost Steadfast 1 Shub, Mutable, Each Mi-Go character gets +1 skill, Action: pay 1 to have Fungal Growth become a Mi-Go character with skill 1 and I until the end of the phase.
On a side note: Most of these CCG cards are from the Forgotten Cities expansion. In that expansion there are a ton of cross-faction cards - similar to what Shangfu posted about in the General Discussion forum - that have some interesting abilities. None seem overly powerful, but help reinforce certain dual-faction themes (such as Yog + Mi-Go).