Flash Powder are a volatile, glittery dust that crackles, sizzles, and creates a blinding flash when hurled into the air. It's useful when it comes to defending against dark magic, however it is unknown whether or not it has any effect on light magic. Fablehaven caretakers can find a small barrel of Flash Powder in the Secret Attic. Flash Powder is not as safe to use as the Magical Salt, but is more effective.

In Grip of the Shadow Plague, flash powder was used as protection from the darkened creatures, such as the shadowy Fairies.

Source

• Grip of the Shadow Plague (Fablehaven #3)
• The Caretaker's Guide to Fablehaven