Courses Projects

Human Computer Interaction 2010

Game Mechanics 

Game mechanics - the procedures and rules of your game. Mechanics describe the goal of your game, how players can and cannot try to achieve it, and what happens when they try.

1) Space

Space - defines the various places that can exist in a game and how those places are related to one another. Spaces can be continuous or discrete.

  • what are the boundaries of the space?
  • how many dimensions does it have?
  • are there sub-spaces? how are they connected?
  • is this world better than the real world?
  • is this world simpler that the real world?

2) Objects, Attributes and States

Objects, Attributes and States - a space has objects (car) in it, objects that have attributes (maximum and current speed), each attributes having a current state (200km/h, 90km/h).

  • what are the objects in the game?
  • what are the attributes of the objects?
  • what are the possible states for each attribute? What triggers the state changes for each attribute?
  • what states are known by all players?
  • what information does the player need that isn't obvious just by looking at the game world?
  • when does the player need this information?
  • how can this information be delivered to the player, so it doesn't interfere with player's interactions?

Game objects usually have many attributes and states, so it is often useful to construct a state diagram for each attribute to make sure you understand which states are connected to which, and what triggers state changes.

By implementing these state transitions in computer code, you automatically forbid illegal transitions.

From The Art of Game Design by Jesse Schell

See also: Role-Playing Games Design Patterns by Whitson John Kirk III

3) Actions

Actions - the "verbs" (protect, build, move, jump, shot, avoid) of game mechanics, representing the base actions a player can take.

  • some verbs may act on multiple objects;
  • goals can be achieved more than one way;
  • what does it mean to make progress in the game?
  • what are the operative actions? what are the resultant actions?

4) Rules

Rules - define the space, the objects, the actions, the consequences of the actions, the constraints of the actions and the goals.

  • what is the problem the game ask the player to solve?
  • are the rules fair enough for the player to continue solve the problem?
  • do the players feel in control and powerful?
  • what are the rewards and punishments this game delivers?

5) Skills

Skills - every game requires players to exercise certain skills (physical, mental, social skills).

  • what skills does my game require from the player?
  • are the required skills real or virtual?

6) Chance

Chance - is essential part of a fun game because chance means uncertainty, and uncertainty means surprises. Chance requires interactions between all the other mechanics.

  • what in the game is truly random?
  • do players have the opportunity to take interesting risks in the game?
  • what is the relationship between chance and skill in my game?
  • does the player always choose the option with the highes expected value?

Character Profile 

  • name
  • concept sketch
  • personal backstory
  • relations with other characters
  • primary desire
  • role in the story
  • occupation
  • transportation
  • weapons or artifacts
  • physical description:
    • gender
    • ethnicity / species
    • age
    • height, weight, build
    • injuries
    • wardrobe
    • pets
  • positions on in-game controversies
  • group/ guild membership
  • musical theme
  • color theme
  • etc.


  • in most games, level represent a discrete change in difficulty
  • in games that have a strong and primarily linear progression, levels are generally areas of a larger world
  • games with location-based levels, create maps that show the connectivity of the level
  • levels accommodate the player's flow through the area and influence his strategy, resources and playing options
evalica 2010