Activate Mystic Sanctuary and Stonespeaker Crystal by tapping them, adding 2.
Cast Ghostly Flicker either from your hand or from the top of your library by paying 2, blinking Mystic Sanctuary and Stonespeaker Crystal.
When Mystic Sanctuary enters untapped, it triggers, putting Ghostly Flicker from your graveyard onto the top of your library.
Repeat.
This brilliant engine turns a humble land and a mana rock into an endless loop by leveraging the top-deck manipulation of One with the Multiverse. With the enchantment letting you cast spells straight from the top of your library, you cast Ghostly Flicker to blink both Mystic Sanctuary and Stonespeaker Crystal. As Mystic Sanctuary enters the battlefield untapped, its triggered ability lets you seamlessly place Ghostly Flicker right back on top of your library to repeat the entire process, while Stonespeaker Crystal conveniently funds the blue mana needed for the flicker.