Zombieees is a chaotic wacky supernatural game where you play as zombies, with a quick adventure generator table you can use as inspo to flesh out. Super simple mechanics and vibes, designed to be easy to pick up for new players and kids. I also wrote an adventure module for this where you play zombie elves in a classic Halloween/Christmas mash up too if you want further reading.
Cryptid Keeper and Prehistoric Keeper are cozy games where you take care of critters and shenanigans happen. These also come with events generators but it would be super cool if you wanted to write an adventure with the premise(s).
All three of these games are PWYW and you are free to use them for this jam if you wish to, just remember to credit with attribution and you're good!