Complex sentence: Typhoon Phanfone and Typhoon Vongfong (Vongfong is the most powerful tropical cyclone of 2014, and the most intense since Typhoon Haiyan) made landfall Japan in October, both they cost $100 million in damage and killed 20 deaths.
Split into simpler sentences: Typhoon Phanfone and Typhoon Vongfong was the most powerful tropical cyclone of 2014, and the most intense since Typhoon Haiyan. Both Phanfone and Vongfong cost $100 million in damage and killed 20 deaths.