If you don't mind me asking, what's the source Public Domain work off of which this game is based?
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Awesome! So it's definitely eligible! Sorry, it's just that some of his other works were after 1925 so I just wanted to make sure what you were doing was legal in the US (it's legal most everywhere else, for sure)!
EDIT: However, looking through on Wikipedia's search terms, I think this work may not be public domain in the US, because it didn't comply with formalities before 1926: https://commons.wikimedia.org/wiki/Help:Public_domain#Published_outside_the_Unit...
EDIT: No, I was right the first time. The US Copyright office says this:
A French short story that was first published without copyright notice in 1935 will be treated as if it hadSo you're good!
both been published with a proper notice and properly
renewed, meaning that its restored copyright will expire
on December 31, 2030 (95 years after the U.S. copyright
would have come into existence).