Invitation to Play
One of the most important elements of a game is the
invitation to play. It can take a number of different
Guitar Hero Controller
Number of Players
A game designed for one player is different than one
designed for 2, 3 or 4 players.
A game designed for a specific number of players is
different from one for a variable number of players.
Single Player vs. Game (Player vs. Environment)
Player vs. Player (Head-to-Head)
Multiple Individual Players vs. Game
Unilateral Multiplayer (One vs. Many)
Multilateral Competition (One vs. One vs. One…
Objectives (or Goals)
Objectives give players something to
strive for. They define what players are
attempting to accomplish within the
rules of the game.
Ideally, they should be:
Obtainable, but challenging to reach
Worthy of obtaining
Immediately replaced by new goals
The Lens of Goals
What is the ultimate goal of my game?
Is the goal clear to players?
If there is a series of goals, do the players understand
Are the different goals related to each other in a
Are my goals concrete, achievable, and rewarding?
Do I have a good balance of short- and long-term
Do players have a chance to decide on their own
Jesse Schell, Lens #25
Procedures are the methods of play and the actions
players can take to achieve them.
One way to think about procedures is:
Who does what, when, where and how.
Types of Procedures
Set Up or Starting Action: How to put the game
Progression: Ongoing procedures after the starting
Special Actions: Available conditional to other
elements or game state.
Resolution, or Resolving Actions: Bring gameplay
to a close.
The Lens of Actions
A game without actions is like a sentence without verbs – think
about what your player can do and what they can’t and why.
What are the operative actions in my game?
What are the resulting actions?
What resultant actions would I like to see? How can I
change my game in order to make those possible?
Am I happy with the ratio of resultant to operative actions?
What actions do players wish I could do in my game that
they cannot? Can I somehow enable these, either as
operative or resultant actions?
Jesse Schell, Lens #24
Rules define game objects and allowable actions by
In digital games, rules can be explained in the
manual or they can be explicit in the game itself.
Rules Defining Objects and Concepts
Board games generally define their objects explicitly as part of their rules
Digital games can have objects made of a fairly complex set of variables
that the player might not be aware of.
For example, consider this ogre in WarCraft II
Cost: 800 Gold, 100 Lumber
Hit Points: 90
Rules Restricting Actions
Rules restriction actions can fix loopholes in a game, such
as not allowing a chess player to place their king in check.
Restriction rules might overlap other game elements such
as rules specifying the size of a football field or the
number of players on a team.
Restrictions might also keep a game from becoming
unbalanced in favor of one of the players, such as rules
preventing strategy game players from building high level
combat units until they acquire resources to build other
Rules Determining Effects
Rules can trigger effects based on certain conditions.
Creates variation on gameplay. For example, if
the player can’t answer the question correctly, the
other players have a chance to answer.
Can help get the game back on track. For
example, if the player runs out of health, return
him to the nearest waypoint.
Too many rules might make make the game too
complicated for the players to understand.
Leaving rules unstated or poorly communicating
them might make players feel confused or
Rules should be consistent with the game’s
The Lens of Rules
What are the foundational rules of my game? How do
these differ from the operational rules?
Are there “laws” or “house rules” that are forming as
the game develops? Should these be incorporated into
the game directly?
Are there different modes in my game? Do these
modes make things simpler or more complex? Would
the game be better with fewer modes? More modes?
Who enforces the rules?
Are the rules easy to understand, or is there confusion
about them? If there is confusion, should I fix it by
changing the rules or explaining them more clearly?
Jesse Schell, Lens #26
The Lens of Emergence
Emergence, or depth, is the number of decisions a
player can make.
How many verbs do my players have?
How many objects can each verb act on?
How many ways can players achieve their goals?
How many subjects do the players control?
How do side effects change constraints?
Jesse Schell, Lens #23
Complexity vs. Depth
Extra Credits: Depth vs Complexity
Resources are assets that are used to accomplish
the game’s goals.
Resources must both be useful and be scarce (or
they lose their value).
Managing resources and determining how and when
to control player access to them is a key part of a
game designer’s job.
Examples of Resources
Conflict keeps players from achieving their goals
directly through rules, procedures, situations, and
This forces the player to employ a particular skill or
range of skills.
Conflict makes a game more enjoyable by creating a
sense of competition or achievement.
Sources of Conflict
The Lens of Conflict
What skills does my game require from the
Are there categories of skill that this game is
Which skills are dominant?
Are these skills creating the experience I want?
Are some players better at these skills than
others? Does this make the game feel unfair?
Can players improve their skills with practice?
Does the game demand the right level of skill?
Jesse Schell, Lens #27
Boundaries separate the game from everything that
is not that game.
These boundaries can be physical – like the edges of
an arena, playing field, or board game – or they can
be conceptual, such as the social agreement to play.
The Lens of Functional Space
Think about the space in which your game really takes
place when all the surface elements are stripped away.
Is the space of this game discrete or continuous?
How many dimensions does it have?
What are the boundaries of the space?
Are there sub-spaces? Are they connected?
Is there more than one useful way to abstractly model
the space in the game?
Jesse Schell, Lens #21
The outcome of a game is its end state – usually a win,
loss or sometimes, a draw.
There are a number of ways to determine outcome, but
the structure of the final outcome will always be related to
the player interaction patterns and the objective.
Many two-player or two-team games are called “zero sum”
games, because there is one winner (+1) and one loser (-
The outcome of a game must be uncertain to hold the
attention of players.
However, some games go on indefinitely and reward
players in other ways to keep them playing.