Complex sentence: Cruel and violent but at the same time a great strategist and expert warrior who became immortal thanks to a Star Soul Jewel created by Daitanix, using the monster to gather a crew by offering them long life.
Split into simpler sentences: Cruel and violent but at the same time a great strategist and expert warrior. He possesses an immortal body, thanks to a Star Soul Jewel created by Daitanix, using Daitanix to recruit his followers by offering him long life.