https://www.techdirt.com/articles/20210123/10253846107/gaming-like-1925-last-week-to-join-public-domain-game-jam.shtml

It's now been almost a full month since works published in 1925 entered the public domain in the US, and that means we're nearing the end of our public domain game jam, Gaming Like It's 1925 — but it's not too late to get involved! After all, plenty of game jams only run for a couple of days, and you've still got an entire week to cook up an analog or digital game based on newly-public-domain material and compete for one of our great prizes.

Check out the game jam page for the full rules and some links to public domain works you could draw on, as well as game design tools for designers of all experience levels. Even if you've never tried making a game before, a week is plenty of time to learn the basics of Twine or Story Synth, and anyone can try their hand at thinking up a roleplaying or party game — we've had winning games that are nothing more than some rules in a text document.