From the books to your workbench

Build the Devices

Every Seer Frights book has a device the villain built. We show you how to build your own. For real. With stuff from your junk drawer.

⚠ DON'T BUILD ALONE ⚠

She watches — and so should your adult. Soldering irons are hot. Batteries can short. Find an adult who knows which end of a soldering iron to hold. Learn from an Earl.

The Projects

Pick a book. Build the device. Scare your friends.

Don't Go Into the Swamp

From Don't Go Into the Swamp

The Swamp Glow

A glowing green puck that sits in shallow water and pulses like something alive. Version 1 is just an LED, a battery, and a plastic ball. Version 2 adds a timer chip for a 2-hour-on, 10-minute-dark cycle.

Build It Parts
Don't Ride Route 13

From Don't Ride Route 13

The Route 13

A pressure strip hidden under a seat. Someone sits down — the device lights up. Version 1 is an LED and a battery. Version 2 adds an ATtiny85 for a 5-second fade.

Build It Parts
Don't Open the Door

From Don't Open the Door

The Three-Knock Device

A tiny piezo disc taped to a surface that clicks when you press a button. Tape it to a door and the door becomes a speaker. Version 1 is manual. Version 2 auto-ticks.

Build It Parts

Before You Start

Every project has three versions. Pick the one that matches where you are.


Version 1 — stuff from around the house. An LED, a battery, some tape, and maybe a plastic ball from the craft store. No soldering. No wires. Ten minutes, tops.


Version 2 — real electronics. Chips, capacitors, resistors, soldering. More like what the villains actually built. You'll need an adult who knows what a capacitor is. If they don't, find a different adult.


I learned this from a library book and a retired electrician named Earl who lived two streets over. Earl had all his fingers. Learn from an Earl.

⚠ Never build alone. Adult supervision required.

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"We saw it . . ."