Game Writer Rick Stemm gives the crashiest of crash courses
This is Rick Stemm, creative lead of Heroes Must Die. In addition to writing a novel's worth of dialogue for this story-driven game, I'm also a professional playwright, and yes, even brought this game to theaters.
I thought I'd use my experiences both on Heroes Must Die specifically and my career as a writer in general to offer the pro-Unity community (that rhymes!) some tips. I'll briefly cover process, tips, tools, and an example. I hope this helps you in your work. And I hope you check out how we implemented it in Heroes Must Die!
Like nearly every creative endeavor, the basic pre-production, production, post-production holds true for game writing too. In this case we have outlining, writing, and rewriting.
Outline - I cannot stress this enough - map out your story before you dive into it. Sure, feel free to write snippets of dialogues, sample scenes, and other spitballing to get the feel down. But at the very least you should have an outline or treatment mapping out the beginning, middle and end. This could be an outline or a flowchart (more on flowcharts later) and should be a page or two. Do this in conjunction with your design document. Make sure your beginning establishes character, setting, plot, and tone. Outline the basic story beats throughout the middle. And know where it's going to end up. Yes things are going to change but dammit, do this step.
Writing - The slog! At some point you have to sit down and do it. In a bit I'll talk about some specific tools, but regardless of what you use you need to get everything down. The outline will make this go much smoother. And you'll be rewriting heavily, so don't worry about the first draft being good. Just get it down. Feel free to take the famous author route (be drunk while doing so), the game developer route (jittery on caffeine while doing so), or the mythical sober route.
Re-Writing - An old maxim in Hollywood is 'writing is rewriting.' That's extra true here. The story will change as the gameplay, art, music, and more get developed. So adapt as needed to fit with the whole of your game. The layout of levels, appearance of characters, inspiration of score, or limitations of programming will often change the story. Plus you'll have a lot of typos. Make sure that's part of QA, or hire a writer from a local college to give it a go.
I used an old-fashioned corkboard to plot out the story of HMD. Even though we cut extra branches this was immeasurably helpful as a guide throughout.
There's nothing wrong with using Word or even, gasp, physical writing implements for the early stages. But at some point you'll need digital tools useful to video game writing. Here are some I've found helpful.
Flowcharts - These generally make more sense than documents for game writing. This allows you to account for different branches if players can explore or make choices. It allows for branching dialogue. And it allows for non-writing components that are still part of the narrative to be mapped out. For example, you can note where combats, puzzles, etc. pop up in the story flow. Programs such as Omnigraffle and services such as LucidChart are invaluable for using flowcharts to map out game stories. Again, the more you do this in conjunction with design, the better.
Unity Plugins - Hey, this is a Untiy site, and man, they really help. Many narrative issues, such as branching dialogue, have been solved already by talented programmers. Make use of what they have to offer! For example, Dialoguer by Tony Coculuzzi of Cuphead worked wonders for us. (Disclaimer: I don't know him personally but his tool is awesome so happy to feature it!). Save yourself the headache and use excellent tools already made with this media in mind.
Your Team - Don't forget to feedback from the rest of your team. In a good game, like all collaborative peices of art, the whole should be greater than the sum of its parts. The art, music, gameplay, and design should all influence the writing, and vice versa. I can't tell you how many times I'd tweak story and character to incorporate some amazing piece of art or music our team did, or to work in jokes our programmer came up with, or to fix problems I couldn't see but someone with a wider view could.
HMD dialogue in Dialoguer
Finally, I am just going to run you through what I did, step-by-step, to write Heroes Must Die.
Outline the basic story with a corkboard flowchart to get story flow, and write a sample scene in Word to get character, humor, and tone down.
Use this to set basic creative feel to guide artists and composer.
Use Lucidchart to map out story flow of every level, including major story moments (cut scenes, etc) and gameplay moments (combat and exploration).
Lay out a rough of the level in Unity.
Using the rough level as a guide, write all dialogue in the level in Dialoguer.
Lay out the level in detail with events, combats, NPCs, etc. assigning dialogue and story scenes on the way.
Rewrite story based on level flow.
Adjust level flow based on story. Repeat 7-8 as needed.
Repeat for all levels in game.
Fix 10,000 typos found by QA and editors.
Hopefully that helps give some basic structure to your work crafting your own wonderful narratives in this insane media. Now all you have to do is write a game that's good.