The MegaJam rules let you use Fab assets you have the licence for, as long as you note them in your submission.
So here is a free one. 33 game sound effects from 12 of our packs, $0 on both the Personal and Professional licence:
Most of our sounds are made with ElevenLabs and edited by hand.
We also run our own jam that weekend on itch.io, Outta This World Sound Jam #1, 13 to 16 November. Any engine, use five of our sounds, and the top three games each get our full library of 1,007 sounds. Your MegaJam game can enter ours too, as long as it uses five of our sounds. Free to enter:
Outta This World Sound Jam #1 - itch.io