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: Javelins and Throwing Spears includes new and varied types of magical and mundane javelins. New feats, class options, archetypes, and rules make javelins more accessible and more powerful than ever. Additional rules for javelin use in mass combat are included, putting this iconic battlefield weapon into the hands of your armies!