Hi darksand123, the current version of Upheaval (0.0.15) already has music and SFX! If you want, you can buy the early access alpha version right now here on itch.io, or you can wait until the game is fully released (I’ll increase the price after the full release). The free demo will always be available, and it should have more content the closer the game gets to release.
Let me know what other questions you have! 😄 Thanks!