I had to admit that Facebook games could be fun. But FarmVille? Really? I plant pretty flowers in my back yard (and forget to water them, so they die), but I have no interest in owning a small farm or playing farm simulations. Tractors do not appeal to me. And yet ... a massive audience was enjoying this game and telling the world about it.
I had to bite the bullet and play the game. It was my duty as a game designer.
So I now have a flower and fruit tree farm in FarmVille. And here's my truly shocking confession - I have quite a bit of fun there. No, I wasn't brainwashed. Game design principles and human nature provide some perfectly sensible reasons Farmville and other Facebook games work as well as they do.
To realize that, I had to let go of some of my preconceived ideas. For instance, just because MMOGs hadn't figured out how to make farming fun for me didn't mean that nobody could. FarmVille managed to make the mechanic of waiting for crops to grow into something more interesting than being held hostage by a boring progress bar. The crops change over time - the art goes from seeds to seedlings to mature plants, and crops like grapes are staked up like a vineyard, rather than being identical to, say, wheat.
FarmVille and other Facebook games use the passage of time and the rhythm of frequent absences and returns (the way people naturally use Facebook already) to reward players who keep track of when they need to harvest crops.
Other rewards throughout the more advanced Facebook games use the classic pull-the-lever-and-see-what-I-won mechanic so popular in slot machines. I like to think of it as the "click-surprise!" mechanic. (That's my own technical term. Feel free to start using it in game design lectures.) The "mystery box" or "mystery gift" is frequently passed back and forth between friends. I now have a chicken that lays "mystery eggs" in FarmVille. I never know what I'll get when I open one of these.
In another of my favorite Facebook games, Birdland, I can breed birds and never be entirely sure what the offspring will look like. I'm often pleasantly surprised. They've made the unpredictability of genetics into an intriguing (for me) game mechanic.
Other not-so-revolutionary elements make Facebook games fun as well. Another key to making Facebook games fun is surprisingly good AI. In Happy Aquarium, I get a kick out of watching these adorable cartoon fish behave like real fish - schooling, circling, mobbing the food. In FarmVille, my avatar navigates a complicated landscape with ease. This is neither trivial to implement nor unimportant to gameplay. Being annoyed when I'm trying to get my reward kills the fun super fast.