From the publisher's website: Onslaught at Arda I is an adventure supplement for the Star Wars: Age of Rebellion Roleplaying Game which explores the themes of desperate struggles, tenuous alliances, and an overwhelming enemy. This 96-page adventure is set at Arda I, a secret Rebel Base, and features mass-combat rules that Game Master’s can use to bring large battles to life, along with in-depth gazetteers that cover the Arda I base, and all-new adversary and vehicle profiles!