Complex sentence: The narration is omniscient and is nearly always fixed on the life of Hilarion, when it deviates, there is a switch in tone which fixates obsessively on the social and economic problems of the world.
Split into simpler sentences: The narration is omniscient and is nearly always fixed on the life of Hilarion. When the narration deviates, there is a switch in tone which fixates obsessively on the social and economic problems of the world.