Fallout 4 mod uses voice AI to add sensible reactions, more RPG-like choices

Modders can change many things inside their favorite games, but dialogue from professionally voiced characters hasn’t been one of those things—at least until recently. AI voice generation could open up new modding avenues for some games, as it has already done with one Fallout 4 mod package.

Roleplayer’s Expanded Dialogue (RED) is listed in the NexusMods catalog as a “Massive expansion of vanilla dialogue,” adding more than 300 entirely new lines of dialogue to the game. Those lines aim to solve an issue near to the hearts of fans of Fallout 1, 2, and New Vegas: role-playing. If you’re playing as a ruthless jerk, a brilliant nuclear scientist, or a strong but dimwitted dolt, you’ll see more dialogue options that reflect this. Mechanically, the roll-the-dice speech “checks,” which are based solely on your charisma level in the default game, can now be unlocked using related traits or skills.

They’re not just new labels on existing dialogue, either. RED, created by NexusMods user ProfMajowski (and first seen by us at PCGamesN), says it used ElevenLabs voice AI to generate its more in-character lines. The results can sometimes “sound a little ’emotionless,'” the creator writes, but “otherwise they basically sound like the real thing.” Nothing your character can newly say now will change the game’s mechanics or reactions, but it should sound a bit more in character.

It remains to be seen whether tweaking existing voice files with AI to create new sound-like lines will hold up to legal and copyright scrutiny or whether the new material can claim its own copyright.

Modders who wanted to remake Fallout 3 inside the engine of Fallout 4 were forced to shut down in 2018 after Bethesda advised them that the voice files the mod would have transferred and transformed were not even fully owned by Bethesda itself, opening the unpaid team to legal liabilities. Modders from that point onward tended to seek out their own voice talent, usually working for free, including Fallout: London, Fallout: New Vegas: The Frontier, and others. At the moment, you’re certain to get better and more lived-in results from voice actors, but AI results may soon be good enough for modders looking to move more quickly on large projects—if they can legally do so, of course.

I haven’t had the chance to kick the tires too much on the RED mod, owing both to the dependency traps of trying to line up a new mod in the Vortex manager, and the fact that you have to play a lot of Fallout 4 in a new, mods-enabled game before you meet characters with truly interesting things to say. Still, the opportunity to hear a strong, agile, but incredibly dumb wastelander make his way across burnt-down Boston makes a replay mighty appealing.