At it's core, it's not about the story or the mechanics but the player's game-play experience. That is what ought to drive the game design process.
Where to begin when designing a Videogame?
You could start anywhere. Maybe try and get some of the story world in place. Maybe make a prototype to demonstrate some cool mechanics. Maybe create some concept sketches to inspire the design process.
Whatever your approach is, you ought not to miss out on deciding one key aspect that's necessary for any medium of entertainment.
There are many ways to describe this: 'The essence of the game'; 'the tone of the game'; 'the very nature of perceived experience that you wish your audience to have when they sit down and invest time with your product'. Despite the lack of an apt definition, designers have come to recognise the need for this unifying factor in order to orchestrate the end to end design process.
Maybe it is how you want the player to feel once he/she puts down the game. For example:
The feeling of accomplishment after having solved a series of puzzles.
The feeling of guilt for having mindlessly slaughtered hoards of enemies who actually didn't mean any harm.
The feeling of curiosity about how the narrative could have been different had the player made a few choices differently.
Maybe it is a philosophical idea that you want the player to contemplate upon while playing the game. For example:
Maybe it is just a perspective of life taken from a specific viewpoint. For example:
What is it like to be a fly and goof around in a messy living room?
What is it like to become the president of a country?
What is it like to be one of the few survivors of an apocalypse?
All you need to make sure is that the desired player's gameplay experience remains consistent throughout the game's development. Furthermore, all the design decisions pertaining to the narrative, the art, the music or the gameplay need to adhere by the previously decided gameplay experience.
I shall call this entity, the desired gameplay experience or just the desired experience in some cases for reference within this text.
The above diagram demonstrates how the 'Desired Experience' is the constant that ought to be decided at first, and then all other aspects of Game Design, the variables, need to adhere to the desired experience.
Deciding the nature of the gameplay experience at the beginning (and not at a later stage of game development) helps the designers to abide by a unifying factor and not go off road while designing the various stages and aspects of the game. Once it has been identified, it can be modulated and enhanced in terms of details as progress is made in the project.
What is there to gain by deciding on a desired gameplay experience at the beginning of the game design process?
A game at the end of the day is a product for entertainment. It allows the player to slip out of reality momentarily and get invested in the fictional yet fun world of the game. When this is the objective, player immersion becomes extremely vital.
For players to be immersed, there needs to be one enticing and thought provoking idea that is central to the game and that holds the players' attention, keeping them engaged for a prolonged duration of time.
This idea is strong when it is reflected by most if not all the entities of the game.
Imagine you are making a game that has the central idea of horror. If you want your players to get immersed then you ought to imbibe elements pertaining to the theme of horror into the various constituents of the game like the environment, the NPCs, the art, the lighting, the music, and most importantly, the interactions.
Now what do I mean by imbibing horror elements? Isn't that common sense?
Well, not exactly. In fact, it is a well calculated strategy. Imbibing these horror elements have the end objective of arousing certain key emotions and instincts in the player. Fear, Survival, and Hesitation are examples key words that one might associate with horror. As progress is made in the game's development, it gets very helpful to add to the decided theme of the game with more and more relevant key words and ideas.
Imagine you need to make a level on the streets of a city. Building a visually pleasing level in a 3-D modelling software is easy. The challenge is to enhance the level in accordance to the decided theme. In this case, the streets can be filled with mist so that the visibility is poor. Not all the street lights are functional and some keep flickering. Subtle details like these add to the idea of uncertainty and loneliness; thus looping back to the theme of horror.
Maybe the game requires the player to move around the map and collect certain resources. What would you have the player collect? Money? Weapons? Family pictures? Maybe the answer lies in the mechanics of the game. If you pause for a moment and recollect the theme you intended to provide your player with, you'll remember it was about horror and survival. The players ought to be collecting resources like water, food or fuel to survive a post apocalyptic setting. This reinforces the emotion of survival and helps in keeping in-game activities relevant to the theme.
If you as game designers intend to increase players' immersion, then taking design decisions that are informed by a previously established theme (desired gameplay experience) definitely pays off.
Besides improving upon immersion, having a central idea that is the core of your design prevents you from going astray.
Two of the main benefits of establishing a desired player experience before heading into the game development process are:
1. It helps increase player immersion
2. It keeps designers from going astray along the development process.
Imagine you decided to create a game that focuses on protecting your family and being there for your loved ones. What would you do, if a collaborator, at a later stage of the development process, comes up with a bad-ass weapon concept that can be found in the ancestral home of the protagonist?
Okay maybe a pass.
Later on, imagine another collaborator who falls in love with his concept sketches of a hidden underground temple that belonged to an ancient civilization from where the ancestral sword must have originated.
Well this is getting hard to keep track of. .
The next thing you know, your project would be all over the place with all these so called cool ideas and you'd seriously have to consider dropping your original family-protecting experience plan in favor of a mix of diverse and possibly conflicting ideas.
I am not discouraging the influx of ideas from the rest of the team. What I am trying to emphasis on is that if brain storming sessions occur before entering the laborious production process, then you'd be clear on the objective for the game project the rest of the way. Having a theme that will hold all the parts of the game together as a cohesive whole will prevent designers from assembling designs that don't go well together.
"What may go wrong if I don't bother with defining the player's game-play experience first?"
Well a number of things. Here are some to give you an idea:
You might go on to write page after page of your awesome game story but might later struggle to build the mechanics around it that do justice to the story.
You might come up with a lot many iterations of character visuals or weapons or maps that might not fit together meaningfully.
If you are working in a group then your collaborators might not be on the same page as you when you discuss a design / usability / implementation issue.
You might have to abandon a lot of work that initially seemed very critical but later turned out to be redundant or even irrelevant.
Your objective with the project will begin to undergo so many changes that the end result might be a mix of possibly diverse and conflicting ideas and themes.
It doesn't work well when all the constituting design processes like music composition, sound design, level design, story creation and mechanics creation occur independent of each other. A digital game needs to be viewed not as a combination of visuals, story, music and mechanics but as a singular unit that provides a meaningful player experience as a cohesive whole.