The rules are on the same page I linked (www.indiegameawards.gg/faq), under the “Game Eligibility” tab. Regarding AI, the document contains a grand total of one sentence:

Games developed using generative AI are strictly ineligible for nomination.

I’m assuming the definition of what that entails is “at their discretion”, meaning whatever they feel like at the moment. I see that sentiment reflected in this thread too.

Unfortunately the boundary between “AI” and “not AI” is the polar opposite of sharp and well-defined. I’ve used Allegorithmic Substance Designer a lot for CGI work (before Adobe ate the devs; fuck Adobe, all my homies hate Adobe), and it contains a lot of texture generator algorithms from simple noise to complex grunge textures. Things like Perlin noise and Voronoi diagrams are well-known algorithms. What about an algorithm that uses real-world samples? Machine learning is not the same as AI, so is that allowed? Where’s the line? I’m reasonably certain that everybody has a different answer based on different criteria.

I gave them the benefit of doubt and assumed that they had defined the exact line of what is and isn’t allowed, but apparently I was wrong.