This ingenious engine centers around Steward of the Harvest, whose triggered ability exiles Gaea's Cradle from your graveyard and grants its devastating mana-producing activated ability to your creatures. To make this work, Singing Bell Strike enchanting the Steward serves a dual purpose: it locks down the creature while granting it a specific "{6}: Untap this creature" ability. By using the borrowed power of Gaea's Cradle to tap for massive amounts of green mana, you can easily pay the {6} cost provided by Singing Bell Strike to untap and repeat the process endlessly.