Complex sentence: The Dynamic Family is forced to abandon New York, which is now overrun with plant life thanks to the Green Lama; the Lama relocates the people of Shangri-La to New York, which he dubs New Shangri-La.
Split into simpler sentences: The Dynamic Family is forced to abandon New York, which is now overrun with plant life thanks to the Green Lama. The Lama relocates the people of Shangri-La to New York, which he dubs New Shangri-La.