Complex sentence: Sierra On-Line's 1992 adventure game "King's Quest VI" has an open world; almost half of the quests are optional, many have multiple solutions, and players can solve most in any order.
Split into simpler sentences: Sierra On-Line's 1992 adventure game "King's Quest VI" has an open world. Almost half of the quests are optional, many have multiple solutions, and players can solve most in any order.