Most of the time involved in playing any game is spent waiting. In a turn based board game each player waits for the others in sequence. Even in a timed chess game the actual portion of the game spent moving a piece from one square to another is much less than the time spent waiting for your opponent or considering your own move. A play clock in football allows for 40 seconds of inactivity between plays that often last less than 5. A tennis match can stretch for hours, with time eaten up not just between volleys, but as one player waits for the ball to be returned (or not) and then moves into a new position and waits for the fraction of a second it takes the ball to reach him. Even in an intense bout of Street Fighter, the actual portion of time spent pressing buttons and taking meaningful game actions is suprisingly low.

Take all the time you want
It could be argued, then, that most of what we call gameplay consists of waiting. Not passive, disinterested idleness, but active, focused anticipation. One key to understanding why a game is fun lies in analyzing the type of anticipation it creates and how a player experiences that expectant state.
Anticipation of the Unknown
The player has no idea what might happen next. While every experience begins with this form of anticipation, it is the least desirable. The power of the mind is its ability to creatively construct predictions, of the future, of the underlying nature of reality, of the internal state of another person, and when it starved of information it becomes inactive. “Anything can happen” is not a statement of possibility, but of unintelligible chaos, and it is a very uncomfortable place to be.
Anticipation of Result
Heads or Tails? Rock, Paper or Scissors? Red or Black? Who wins, who loses? This type of anticipation occurs when we have a stake in the outcome, but no control or predictive insight. We are wired to make sense of the world, and when something resists, it itches. In the absence of actual patterns, people invent them, which is the basis for superstition and our utter inability to intuitively comprehend randomness. Engaging curiosity in this way is a useful tool, especially if failure is not punished, but if it never pays off it turns to frustration.
Anticipation of Evidence
We know the hero is going to save the day and get the girl. Screenwriters understand that their audience wants a comfortable trope and if they violate this tacit desire the focus groups will force a re-write. But we don’t know how, when everything looks impossibly bleak, the hero will turn the tables. We are anticipating the moment where the pattern is revealed, the hidden trump card appears, and our faith in the Hollywood formula is proven correct. This kind of anticipation is present in puzzle games where we know there is a solution, but we aren’t sure what form it will take or how we will discover it. Nothing is more infuriating than a puzzle we know we are intended to solve, but can’t.

The World before Walkthroughs
Anticipation of Action
This is the primary form of anticipation found in games. The player knows that soon it will be their moment to act, has a model for making predictions, and is excited to test that model against reality.
- Queued Action – The simplest form of anticipated action. The player knows what they intend to do and are merely waiting for the opportunity to execute. As soon as the game begins, I will move my Queen’s Pawn forward two spaces.
- Queued Reaction – Preparing to respond to an event, either in the environment or initiated by another player. Because there is only one prepared action, the response time will be as short as possible. The instant they stick their head around the corner, I’m going to open fire.
- Multiple Queued Reactions – Mentally preparing for multiple possible events and focusing on distinguishing between them quickly. If the ball comes to me, I’ll catch it. If it goes to the outfield, I’ll be the cut-off. If it goes toward first base, I’ll cover second.
- Inductive Prediction – Trying to guess what an opponent will do and act preemptively at the right moment. (David Sirlin calls this Yomi, or “knowing the mind of the opponent”.) I bet they are going to try a jumpkick, so I’ll throw my fireball to catch them on the way up.
- Deductive Prediction – Using knowledge of a player’s available actions to reduce the number of reactions that must be prepared. He’s carrying the sniper rifle, so I bet he isn’t going to rush my position.
- Forced Prediction – Performing an action for the sole purpose of forcing another player to make a predictable response, with the intention of capitalizing on it. In fencing this is called a second intention and happens when you are driving an opponent to react to your attacks instead of taking the initiative themselves. I’ll fire at his feet with my rocket launcher, which will force him to jump into the air and leave him unable to dodge my second rocket.
One important aspect of game design is intentionally inserting gaps in the action to allow for the desired anticipation. A simple game that has too few possibilities or happens too slowly will fail to fill the time between actions and become dull or predictable. A game that is overly complex or happens too quickly will cut short the player’s anticipation and feel out of control or chaotic. Giving the player control over the pacing may encourage them to over-think their actions. A small change in the cadence of a game, or providing more or less predictive information, is often enough to change type of anticipation, which is a powerful tool for adding gameplay variety. Understanding and tuning anticipation is crucial to crafting a fun experience, because once anticipation is gone, boredom sets in.