Complex sentence: Richard and Kahlan are tasked with finding the third box and keeping it out of Rahl's hands until the winter solstice, at which time, unless Rahl has successfully joined the three boxes, his life will be forfeit to the magic of Orden.
Split into simpler sentences: Richard and Kahlan are tasked with finding the third box and keeping it out of Rahl's hands until the winter solstice. At which time, unless Rahl has successfully joined the three boxes, his life will be forfeit to the magic of Orden.