Stellaris launched in 2016, since when it has followed the usual Paradox post-launch cycle of regular tweaking accompanied by substantial paid-for DLC expansions. The latest is The Machine Age and focuses on "synthetic ascension" and the promise of eternal life among the stars, adding various new elements to the machine side of the game alongside a synth space queen that says she's going to get us all there.
The DLC's store page spells all of this out then, right at the end, drops this disclaimer:
"We employ generative AI technologies during the creation of some assets. Typically this involves the ideation of content and visual reference material. These elements represent a minor component of the overall development. AI has been used to generate voices for an AI antagonist and a player advisor."
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