Forged by Princess Ancien’s mystical tablet in a fantastical dream realm, Joy emerges as an anthropomorphized blue plush canine companion, awakening to sentience and pledging loyalty to her creator. Alongside Ancien, she clashes against molten terrors like the Colossus and duels within towering Engineheads. Tragedy strikes when Ancien vanishes amidst battle, propelling Joy beyond Heartland’s borders with the king’s blessing. Guided by the enigmatic Katy Caterpillar, she claims the legendary Excalibur from the Lady in the Lake, cementing her destiny as the Prophecied One.

Her journey weaves through interconnected realms, rallying allies like Sprig Plantar and Dumbo to outwit Sphynx Cats and confront foes such as the Sugar Plum Fairy and Hades. A twist of fate reveals Dream, her twin from a mirrored Heartland, as they unravel prophecies entwined with mystical relics. Partnerships with wish-granter Jirachi and warrior Kanaria drive her pursuit of hidden truths.

Parallel to her odyssey lies a deeper legacy—the dream realm mirrors the real-world history of Kokone’s family, with Joy’s plush form embodying a cherished toy linked to Kokone’s late mother. This duality bridges technological ingenuity and heartfelt bonds, anchoring her battles against existential threats like the Queen of Darkness and corporate corruption.

Spin-off sagas test her resilience further: surviving the Hunger Games’ crucible, navigating the Sistar System’s fractured dimensions, and forging uneasy truces with figures like Morgana and General Sweet Mayhem. Each trial sharpens her leadership as she hunts artifacts—a mechanical egg humming with Jirachi’s prophecies—to unite allies against cascading perils.