Complex sentence: A small pounamu stone that has the power to create life and is the mystical heart of the goddess Te Fiti is stolen by the demigod Maui, who planned to give it to humanity as a gift.
Split into simpler sentences: A small pounamu stone that has the power to create life is the mystical heart of the goddess Te Fiti. It is stolen by the demigod Maui, who planned to give it to humanity as a gift.