Jet Set Willy , released in 1985, is a seminal platform game that follows up on the cult classic Manic Miner. In this game, Willy now owns a lavish mansion with over 60 rooms linked together, and must tidy it all before his housekeeper will let him sleep.
The route through the house must be navigated carefully, due to the multiple entrances to some rooms - this is perhaps the first action game where mapping is an advantage. Willy's goal is to clean each room without touching hazards or falling a great distance, as touching a monster or a stationary hazard, or falling a great distance, causes instant loss of a life and places Willy back at the room entrance.
Another innovation in Jet Set Willy is manual protection - a sheet of colour-coded numbers. Players must use this system to manually protect themselves from certain hazards, adding an extra layer of challenge and strategy to the game.