Towards Videogame Variability

Variability denotes the capacity of a game to offer more than one game experience to the player, i.e. the ability of a game not to be constant. There are two levels of game variability: internal game variability and external game variability.

Internal variability denotes the capacity of a game to offer a different experience to the player within the same game instance, from the game start to the game end. A game without internal variability offers only one possible experience during gameplay, i.e., the same player inputs produce the same outputs. Games with internal variability use different methods to add variation during gameplay.

RPGs typically use character development to offer internal variability. Character development enhances the player character’s capacities in function of the player’s progress. The more the player has progressed, the more capable the player character becomes. This implicitly forces the player to keep progressing, in order to explore what the player character can do. Additionally, when the game is finished, the player is implicitly forced to restart the game and optimize the progress to explore all the possible player character’s capacities. 

External variability denotes the capacity of a game to offer a different experience to the player in different game instances, each time a new game is started. A game without external variability offers only one possible overall experience, i.e., always the same game start and always the same end. Games with external variability use different methods to add variation to each game instance.

Some games let the player choose a player character between a set of possible characters. Even if the game has no internal variability, this player character choice adds variability to the overall gameplay experience, implicitly forcing the player to restart the game and choose another character just to check how this little choice affects the entire game.

Therefore, both internal and external variability directly affect replayability. Variability extends the number of game possibilities, and since most players want to explore all what a game has to offer, variability directly enhances replayability.

Unfortunately, the most common trend is to make games longer without investing in variability. The result of extending the duration of a game (metaphorically the length of the game experience) without expanding the variability (metaphorically the width of the game experience) is a constant and linear experience which is closer to a film than a game. Some (hardcore) players would still finish the entire game, but few will choose to replay it since the game experience will remain constant.

How can we add more variability to our games?

Games are complex systems which can be analyzed through different views of interest or game perspectives. Gameplay, control, graphics, AI, level design and storytelling are some of the most self-evident game perspectives. Although variability can be applied to all game elements of the different perspectives, I’m initially focusing on player characters.

A game element can be either:

1. Invariable

2. Variable

                2.1. Pre-generated

                2.2. Random-generated

                2.3. User-generated

Invariable game elements are pre-defined game elements which remain constant. Like it or not, it’s the game element you’re forced to play with. It’s always the same, you cannot choose it. Some examples of invariable player characters include typical story-driven games where there’s a single and invariable player character. The player can choose some minor attributes such as vehicles, weapons or armor, but the character remains constant when you begin and finish the game. In story terms, there’s no character progression mapped to gameplay attributes. On the other hand, CRPGs and JRPG typically offer a single and invariable main player character which can progress and control other secondary player characters.

Pre-generated game elements add a first level of variability to a game. Instead of a single and constant game element, the player can choose between a set of pre-generated game elements. The player choice adds interactivity to the game (Wow! I can choose!). The potential number of combinations adds replayability to the game (What if I had chosen another element? Let’s try it out!). Some examples of pre-generated player characters include Maniac Mansion and most 2D fighting games. Maniac Mansion offers the player 7 player characters to choose from. And typically, 2D fighting games offer the player lots of player characters to choose from. Each character is constant, but at least the player can choose which player to use.

Random-generated game elements are a step further towards game variability. Instead of a choice between a set of pre-generated elements, the player is presented a random set of variable game elements. Although today it’s shamefully a bit out of vogue, randomness can add great variability to a game system. As a well-known example, most D&D-based CRPGS allow the player to create a random-generated main player character (re-rolling the character as much as the player desires).

User-generated game elements dramatically increase game variability. This new level of player choice and creative freedom increases interactivity, replayability and identification (I’ve done it! I love it!). As an illustrative example of user-generated player characters, SoulCalibur 4 allows the player to create customized player characters.

Note that game elements don’t raise so easily the variability ladder. Raising a game element from invariability to random-generation can be a great effort. Consider the simple example of game scenarios in the level design perspective. Shifting from an invariable set of levels to a random-generated set of levels means a ton of work. To make it possible it’s necessary to design the game at a higher level of abstraction. Now it’s not a matter of “this door doesn’t fit in this room” but “where do doors fit in rooms?” which usually requires a lot of thought and a higher level of design effort.

But sometimes it’s not possible (or convenient in terms of identification) to go any further in the variability ladder. Does it really make sense to have a user-generated enemy or scenario? Sometimes it’s enough with random-generated variability.

In either case, games have to climb the variability ladder in order to offer deeper game experiences. Players want a different and thrilling game experience every time they start a new game. Why don’t we give it to them?