Alarms are abstract game elements that provide information about particular game state changes.
Alarms are indicators that can show that important changes in the game state has occurred. This can be that fuel is nearly depleted in a race, a self-destruct has activated, that guards have detected the player's avatar or that an illegal activity has been observed. The activation of an Alarm lets players know that a problem has occurred which likely needs to be dealt with while the de-activation lets them know that they are safer.
Some team-based first-person shooters, such as Return to Castle Wolfenstein: Enemy Territory, include Alarms to inform the players about events that are relevant on a team level, e. g., that a particular goal has been completed or that a certain activity has been initiated by the other team.
Using the pattern
Further, designers may choose either explicit Tools or Controllers to manipulate the Alarms or to have the manipulation of the Alarms as Privileged Abilities for certain types of Avatars or Units. Using Tools or Controllers increases the complexity of the game by allowing such possibilities as deactivating the Alarm when it should not be deactivated, Bluffing by raising erroneous Alarms, and preventing the raising of Alarms by destroying the means to activate them. All these actions increase the player's Freedom of Choice but may make it more difficult to guarantee coherent Narration Structures of games. Having Avatars or Units with Privileged Abilities to raise Alarms may avoid this problem but may break the Diegetic Consistency.
The activation of the Alarm can signify the failure of a Stealth or Reconnaissance goal but can also make the completion of it more difficult by imposing a Penalty. This Penalty is often a Time Limit, the introduction of new Enemies, or directing existing Enemies to the area where the Alarm was raised.
By their nature of trying to get attention to some problematic state, Alarms can cause Time Pressure as they often imply a Time Limit. An alternative to this is to let the de-activation of an Alarm be a goal.
Of course, the pattern can most easily be deigetically be presented in a game as an alarm is some form or other.
Alarms are ways to pass information about activities and states within a game, and as such provide a Game State Overview. When activated by players, an Alarm notifies the players that they have been detected, and this can explain changes in the behavior of Enemies or the introduction of new Enemies within the Consistent Reality Logic of the game. When activated by others, Alarms can notify players of Enemies activities. In both cases, raised Alarms cause Disruption of Focused Attention.
Potentially Conflicting With
This pattern was part of the original collection in the book 'Patterns in Game Design' (Björk & Holopainen, 2004).
Björk, S. & Holopainen, J. (2004) Patterns in Game Design. Charles River Media. ISBN1-58450-354-8.