However, they couldn't carry storylines over. "Each one was a very self-contained short experience" by design; each storyline and setting had to exist in isolation from one another, because the team could not assume that any player would own all four packs. That "short experience" adds up to just 10,000 lines of dialogue across all four, Avellone said – a hard maximum. As a result, Avellone and Obsidian had to pad out the dialogue with "trickery" including mute characters who spoke in hand gestures. "We were only able to get away with that for so long," he added.
More abstract concerns included making sure all the NPCs and storylines had clear impact on the player – as in making sure the player cared about what was going on. Writers identified clear themes motivating everyone's actions in each DLC, like "Rigging the Game" and "Greed as a Savage Force" in Dead Money.
Writers then set in doing research, which entailed an exhaustive period of going through books, movies, and even games that might have similar style or otherwise work as an influence. Examples, again, for Dead Money include Cube, Lifeboat, and Suspended: A Cryogenic Nightmare.
Once dialogue is written, Obsidian stages table reads. However, these don't involve the voice actors; rather, team members each take the part of a character they didn't write, and then go through the dialogue, each noticing where others stumble, mispronounce words or show any other disfluency. This process helps streamline the recording process later, "because studio time is incredibly expensive," Avellone said, "and the last thing you want is some actor spending five minutes debating this line with you to try to get it fixed when you have 300 more lines you still have to read and you have no idea how they're going to get done."