From publisher blurb:
Call to Arms is a book line for players and gamemasters alike. Each book focuses on a different type of item, expanding rules for those items and adding everything from new mundane and magical examples of the item to new character options related to the item.
Call to Arms: Powders and Dusts includes a review of and expansion to mundane, magical, cursed, mythic, and even artifact dusts, as well as new powder based afflictions, new character options, such as blinding attacks, and new rules for infusing spells within powder. Here are the tools to transform a handful of sand into a vicious weapon or devious trap, surprising your enemies (and sometimes allies) with the most basic of materials. Never before has simple dust been so versatile – or so deadly!