Complex sentence: He has been just chosen by his master, Lord Verkapheron, to travel to the forbidding Island of Char, now known as Witchaven, domain of the powerful witch known as Illwhyrin, responsible for plunging Stahzia into never-ending darkness.
Split into simpler sentences: He has been just chosen by his master, Lord Verkapheron, to travel to the forbidding Island of Char. The island, now known as Witchaven, is the domain of the powerful witch known as Illwhyrin who is responsible for plunging Stahzia into never-ending darkness.