I’ve been playing some Jet Set Willy recently.

I never got into the ZX Spectrum much, mostly because it was rare here in the States (as was the MSX, another good older computer). The plot line was simple – Willy has just bought a huge sixty-room mansion. It’s so big that he hasn’t even visited all the rooms yet, but that didn’t keep him from throwing a wild housewarming party for himself. Now all the guests are gone, the house is a mess and Willy just wants to go to bed, but the housekeeper, Maria, refuses to let him until he’s cleaned up every room in the house.

Despite that rather odd plot, Jet Set Willy was well-loved in the Spectrum community. After playing it a bit, I can see why. It was released in 1984, and had two features that were rare in games of that day – determinance and persistence.
Persistence is fairly obvious. The mansion has sixty rooms, each one consisting of a single screen. Every room has a name, and almost all rooms have multiple exits, which lead to other rooms. Almost every room has at least one object Willy has to collect. Therefore, the mansion feels like a mansion – rooms lead to other rooms, and you can go back and forth at will. Which means that it’s possible to map the mansion. And if you pick up an object in a room, that object doesn’t reappear when you revisit the room, because it’s (presumably) in your pocket. Jet Set Willy took persistence one step further – in the space base part of the mansion, there’s a room whose configuration changes based on the rooms the player has visited. Therefore, as you get closer to completing the game, this room fills up with blocks, and the blocks are colored differently depending on whether or not you’ve found every object in each room.

If this doesn’t sound like much, note that Nintendo’s 1984 magnum opus Super Mario Brothers wasn’t persistent at all! Persistence was rare in games in this time period, since it required the machine to keep track of the state of rooms the player wasn’t actually in, and most games didn’t bother. Games that did, like Jet Set Willy, felt more like a coherent experience than games that did not.

Determinance is the opposite of randomness. Whenever the player enters a new room in Jet Set Willy, he is (for the moment) safe. Enemies have predictable patterns, and the player is allowed to stop and watch the enemies before he makes a move. The player won’t ever be killed by some random thing flying in from offscreen that he can’t react to – every part of the puzzle is laid out in front of him and his own skill decides whether or not he can solve it. This doesn’t mean that the game is easy – quite the opposite. But the game is beatable, all it takes is knowledge and skill on the part of the player.

This is another feature that wasn’t common in games of the time. Most computer games were based on arcade games (in spirit if not in actual content). But arcade games are designed to make money, and they do so by making the player lose so he’ll put in another quarter to try again. Therefore it was very common in arcade games to have random things come in and kill the player.

But computer games aren’t arcade games, and Jet Set Willy’s designer, Matthew Smith, realized this. So he threw off that constraint and created a game that allowed the player to take his time and figure the game out.

Both of these advances are important because they allow the player to choose how he wants to play the game. This is vital in my opinion, and I’ll be writing more about it later.