Jet Set Willy is a platform game in which the player moves the protagonist, Willy, from room to room in his mansion collecting objects. The room’s exits may be in any direction, and the objects may be collected in any order. Willy is controlled using only left, right and jump. He can climb stairs by walking into them (jumping through them to avoid them) and climb swinging ropes by pushing left or right depending on what direction the rope is swinging in. The play area itself consists of 60 flick-screen rooms containing hazards (static killer objects), patrolling monsters (killer guardians which move along predetermined paths), various platforms and collectable objects. The collectable items glow to distinguish them from other items in the …
Willy loses a life if he touches an enemy or falls too far, and he is returned to the point at which he entered the room. This may lead to a game-ending situation in which Willy repeatedly falls from a height, losing all eight lives in succession.