Extremely annoying foretell deck

This deck is extremely annoying to play. You'll constantly be checking your exile, checking which supports are foretold, and trying to keep Guardian of Faith OUT of your exile. But maybe someone will benefit from my experience trying to make it work.
Ultimately, it works okay. You usually win by your 6th turn. They key cards are the creatures:

Guardian of Faith
Void Maw
Cosmos Charger
And if you get a bunch of creatures in your exile, and a few foretold tokens on the board, the FIRST turn you cast GoF can end like this:

This is due to some kind of cascade with Cosmos Charger that I don't really understand:

But even an average turn casting GoF ends in Void Maw summoned from exile and self-buffed to 16/17. This means you could probably replace Cosmos Charger with any other creature.
Here's the deck I'm using. Karn (lvl 36) as the plainswalker allows you to exile two cards every turn just from his first ability: