This infinite loop is masterminded by Precognition Field, which grants you the crucial ability to cast spells directly from the top of your library while keeping your draws transparent. You kick things off by tapping Grim Monolith for colorless mana and Mystic Sanctuary for blue, funding the casting of Ghostly Flicker to exile both permanents. When Mystic Sanctuary blinks back onto the battlefield untapped, its triggered ability swoops in to place Ghostly Flicker right back on top of your library, perfectly positioned for Precognition Field to cast it again. Meanwhile, Grim Monolith returns fresh and ready to tap for mana once more, sustaining the loop and generating infinite colorless and blue mana in the process.