This clever loop hinges on Jegantha, the Wellspring and Horde of Notions working in a self-sustaining cycle of sacrifice and resurrection, fueled by Ashnod's Altar and The Fire Crystal. You tap Jegantha to generate the exact five-color mana requirement for Horde of Notions, which then plucks Jegantha straight back out of the graveyard for free. Meanwhile, Ashnod's Altar handles the sacrifice while leaving behind a surplus of colorless mana, and The Fire Crystal quietly grants your creatures haste so Jegantha is ready to tap the very moment it returns.