Complex sentence: Marvin, who is fleeing from Christian missionaries who have taken over his village and are rather unkindly assuring them that their faith in Christianity will get them food, which obviously won't happen, goes into the ship in search of a place to relocate his people.
Split into simpler sentences: Marvin, who is fleeing from Christian missionaries who have taken over his village and are rather unkindly assuring them that their faith in Christianity will get them food, which obviously won't happen. Marvin goes into the ship in search of a place to relocate his people.