Implement Flow in Games


The best way to test out the player-oriented DDA system and methodologies is to create games designed around these methodologies and compare the result between using and not using the DDA

Traffic Light

Traffic Light is my first attempt to create a simple prototype and test whether or not player-oriented DDA helps the Flow experiences.

Traffic Light is designed to be a game with minimal interaction and a test bed for choices based DDA. The only thing a player needs to do in this game is to predict and click the button as late as they can before the red light goes on.

By default, the player has three times to try in each round. If the player won two out of the three, he can keep his total score and go to the next round. If the player failed in one round, he loses the total score.

Between each round the system will ask the player if they want to play faster or slower or stay as the current speed.

On the top left of the screen are lights representing the total times player can try in each round. If they failed it turns red, otherwise it is green. If they have not tried, it shows as black.

The two scrollbars allow players to change the speed and the total times in each round.

The two rows of numbers on the right represent the total score and how many seconds earlier the player clicked the button.

Test Result
Player-oriented DDA based on choices effectively extends the game Flow. It extends a simple timing game’s lifespan from 1-2 minute to about 5 – 12 minutes.

However, the frequent DDA choices broke the player’s Flow. It started offering the player a sense of control, but eventually reduces the player’s control.


FlOw is created to test player-oriented DDA with choices embedded inside the gameplay.

In flOw, the player uses the mouse cursor to navigate an organism through a surreal biosphere where it consumes other organisms, evolves, and advances into the abyss.

The gameplay is intentionally designed to be extremely minimal for easily evaluating the efficiency of the player-oriented DDA system. The only action players can perform is to swim around and eat other organisms in front of its mouth.

Expand Flow Coverage
FlOw uses minimal control to open the door for casual gamers and non-gamers, but still leaves space for hardcore gamers to master it. It offers a wide range of gameplay from simply swimming around and eating to strategically evolving and intensive fighting.

Adjust Flow
FlOw is divided into 20 levels. Each level introduces new creatures with new challenges. Different from traditional games in which players have to complete one level in order to progress to the next one, flOw offers player power to control their gameplay progress. By choosing different food to eat, players can advance to the more difficult level and return to the easier level at any time. The game features a minimal death penalty. If player died in one level, he will be pushed back to the previous level that is relatively easy. Player can also choose to avoid the challenge, skip the level, and come back later.

Embed DDA Choices into Gameplay
In flOw, players can customize their Flow experience naturally through the core gameplay, swimming and eating. By swimming closer to or farther away from other organisms, and eating different types of food, players subconsciously balanced their Flow experience.

Test Result
The current version of flOw is prototyped in Macromedia Flash 8. During the first two weeks after flOw was released online, it attracted more than 350,000 downloads. 

“Addicting” is the most common word its fans use to describe it. FlOw was invited and presented at the annual Experimental Gameplay Workshop during the GDC 2006. It also won the Internet Game of the Month on EDGE magazine, May 2006.

To get a sense of how widely enjoyed flOw is on the Internet, here are some of the quotes from the online community:

“For some reason I can’t stop playing it. It doesn’t make much sense, since I can’t imagine why I would continue to play it, but it’s almost soothing to play. The graphics and sound are amazingly perfect. Try it out, you won’t be disappointed. Unless you think all flash games are wastes of your time.”
Always Beta

"There must be something wrong in playing the whole morning with this evolution game… It has no guns, blood or explosions, but something kept me glued to my seat for a long, long time. 
Fortunately, my critter ran out of food and I was forced to leave it there. Look at my mutations and changes (the best I could get in 3 hours!)”

“Show some appreciation, then, by checking out the lovely, mindful Flow. Set in a clear blue monochrome sea inhabited by Euclidean cellular critters and your own slowly evolving Tinker toy paramecium, Flow sucks you in with its sinuously elegant physics and keeps you hooked on the ever so slightly yet increasingly challenging task of gobbling up your fellow sea bugs. A brick-simple, submarine Pac-Man, Flow pulls off the remarkable feat of feeling as meditative as it is addictive.”
Zen and Art

“Beautiful, relaxing and confusing, Flow allows you to take over the evolutionary steering wheel for a scoop-equipped microbe in a shifting sea of predators and prey.

  • Easy to play
  • Endless
  • Addicting and relaxing
  • Very atmospheric and attractive despite the extremely basic graphics


  • It's addicting like the government putting something in the water supply: you're addicted but you don't know what you're addicted to.

Almost too esoteric for its own good”

Something Awful