Game Development Reference
In-Depth Information
Collusion
Collusion
is a form of cheating in which players who are supposed to be opponents
work together in violation of the rules. The rules of
Monopoly
explicitly prohibit col-
lusion. The fact that the players are all in the same room, and usually have social
obligations to one another, tends to enforce that rule. Unfortunately, you can't
count on those factors in an online game. Some players will join a game with a
deliberate, even avowed, intent to cheat. Because they're playing with strangers,
they have no social relationship at stake, and because they're physically miles
apart, no one can see them do it.
EXAMPLES OF COLLUSION
Computer games seldom have written rules because the designers assume that the
game will enforce the rules automatically: The players simply can't make illegal
moves, in most cases. However, software can't detect certain kinds of collusion
between players.
Consider an online multiple-choice trivia game with three possible answers for
each question. Each player receives the same question from the server and has a
fixed length of time in which to enter an answer. When a player enters his answer,
he immediately learns whether he was right or wrong. Correct answers earn points,
and the player with the largest number of points at the end of the game wins.
Four players can easily collude at this game to guarantee that one of them will win.
They all play on different machines in the same physical location—an Internet
café, for instance. When a question appears, three of the players each immediately
enter a different response—A, B, or C—and the fourth one waits. When the soft-
ware informs one of three players that she is correct, she immediately calls out her
letter, and the fourth player enters it before the time runs out. This way the fourth
player always enters the correct answer. Even with fewer than four players collud-
ing this way, they can greatly increase the odds of winning.
You can easily defeat this form of collusion: You simply don't reveal the correct
answer until the time for entering answers runs out. Players who enter an answer
early simply have to wait to find out whether they answered correctly. But other
forms of collusion can be more insidious. Online poker, for example, can involve
players sharing information about their cards via instant messaging or some form of
physical communication. There is no way for the system to account for external means
of communication. If you offer a prize for the player who wins the greatest number
of chess games in a certain length of time, for example, two players can collude to
play each other, with one always trying to lose to the other as quickly as possible.
DESIGNING TO REDUCE COLLUSION
The designer of an online game must try to anticipate collusion as much as possi-
ble. Unfortunately, experience shows this to be extremely difficult. There are no
