Dialogue in games is a difficult thing to integrate so it sounds natural. Conversations can flow into an almost infinite amount of possibilities, but computers are limited and simply can’t.
In some games, like Dishonoured (2012), NPC dialogue is stilted and repetitive.
However, dialogue in games like Detroit Become Human (2018) show that dialogue in games has come on a lot.
Dialogue has to be written in such a way that it is natural. In a game, this means that it is going to be, to a greater or lesser extent, dynamic. As the player goes through the game, they will meet different people in different situations which will have the effect of making the dialogue different. Detroit Become Human is an example of this, and so is Life Is Strange (2015).
The dialogue choices in a game like this mean the script is going to be very different from the script of a film. A story like this has dialogue written in nodes, rather than a whole script. After a few choices have been made, these get complicated very quick.
In order to affect this type of writing, a technique called ‘bottle necking’ is used. This is where different choices eventually meet in one node and then split off again. An example of this style of writing is the Fighting Fantasy books by Steve Jackson and Ian Livingstone. This excerpt from The Forest of Doom (1983) shows how this works.
From this, the story nodes branch off like this:
You can clearly see a node like 267 is a bottle neck. Lots of ways into that section of the story, but there are only two ways out. Dialogue works in the same way. There aren’t endless possibilities, but it feels like there isn’t. After all, when you get to a bottleneck, you won’t realise as a game player.