Back Tap Banshee

What happens

Double-tapping the back of the phone (which is what happens when you set it down on a table a little too hard) plays a banshee shriek.

Setup

1. No download needed. Open Shortcuts → +, add Play Sound, and pick a scream from Files.
2. Name it something boring like “Utility”.
3. Settings → Accessibility → Touch → Back Tap → Double Tap and pick the shortcut.

Undo

Settings → Accessibility → Touch → Back Tap → Double Tap → None, then delete the shortcut.