In my last game related post I wrote about the mechanics of making a game work. Just because a game works does not mean it is enjoyable to play. In this post I am going to talk about the reward cycle and why some games are so addictive and other either get boring, or were never fun to begin with.

The key concept her is the action-reward cycle. A player makes a decision and then gets some feedback on that decision. Good decisions get rewards while poor ones are either ignored or reduce future rewards. The thing that makes a game fun to play is the balance and value of these rewards.

Before we dig in to far we better talk about what a reward is. A reward is anything feedback a player gets as a result of their input. Not all rewards are equal. Some are very low cost and low value. when you click the mouse in a first person shooter the game rewards wou with some weapon firing. The first time the BFG9000 goes off it is pretty cool, after an hours of play some players might switch to a less powerful weapon just to get a different reward, even if it lowers their ability to kill monsters. Really good games have increasing levels of rewards in a fairly predictable pattern.

The five-second reward: Most video games have some action that the player takes 10 to 20 times a minute. Fire a weapon, run, jump, punch, kick, select a unit, give orders, etc. These rewards are directly tied to control inputs, an the reward is a minimal change in state, though it is often one of the thing that animators spend the most time with. In some ways it is almost not a reward, but actions like these are very important in getting the player to "get in to" the game. Games that lack short period rewards tend to be labeled as slow, while games where the reward is not that great will be calld repeative.

The One Minute Reward: Most video games are built around these rewards, while board games tend to start their reward system here and build onto bigger rewards. In our FPS this reward might be killing a monster. It is a reward that requires the player to have preformed a set of tasks (find monster, aim, fire) but the outcome is still pretty much a done deal. Games that lack a one minute reward are usually though of as repetitive, while games that put too much space in between their one-minutes tend to be frustrating for new players.

The Five-Minute Reward: This is about the point where peril starts to become an issue. Up to this point, following the rules got you rewards, at this level, one must no just have followed the rules but done so "effectively." In an FPS this could take the form of effective use of ammo and avoiding enemy fire. There is traditionally a more difficult task to accomplish (a tougher monster) and a more permanent reward (a power up, advancing to a new level). Games that lack this reward type or make it too infrequent are usually described as a grind.

The 30 Minute reward: At this point times get a little more fuzzy, as to the goals. The pattern on the other hand continues, more coordination of resources and game states is required to achieve this reward, and the reward need to now be something the player knows they want to have happen. This is also the high point for plot. Games that have a strong plot will need to move it forward in about this amount of time or the game will feel frustrating and players will give up for lack of progress. On the other hand the 30 minute reward is what drives further play. Even after the 5 second and one minute rewards have long sense become boring and repetitive, the drive to see what happens next is enough to keep players at it long past bed time. Some games don't get to this point or have a terminate here with the reward being winning the game. These game are usually described as simple or casual (solitaire, free cell). Games that skip or prolong this step too far are often labeled frustrating or a waist of time.

The Renewal Reward: The next challenge is to keep the 30-minute reward fresh. One way to do that is to somehow alter the rules of the game. New settings, characters, dramatic plots twists, changes in game mechanics, or even a new skill path, can refresh old rewards.

Ladders, Tournaments and Status: Another way to keep rewards fresh is to create a little friendly competition. Tese ate the types of things that don't effect the play of the gaem but provide bragging rights.

The Grand Prize: Most single player games at some point have an end where the plot wraps up and the game is won. As long as the game designer can keep the light shining at the end of the tunnel players will often play long after they are board with everything else in order to finish off the plot.

10 Hours and Beyond: There is nothing that says a game has to end at a certain point, but to keep going there must always be greater levels of mastery to achieve. Single player video games tend to run 20-60 hours and have in the neighborhood of 100 levels/phases/etc. With the advent of MMO games needed to last for months or years. The trick here is to have larger games space no just in terms of world space, but plot elements, power-ups quest options, etc. There needs to be a goal to achieve every 1-5 play sessions to keep players coming back. A general rule of thumb is a reward of one level is good about 30 times before something better has to be achieved. As players play longer the space between rewards can be spread out (the 30 minute reward might actually take 3-5 hours for advanced players) but the number or similar rewards that can be tolerated before something better happens shrinks (the same advanced player my start to feel like there is a grind after only 8-10 30 minute type rewards unless there is something better to look forward to.)