From the publisher's website:
Omens of War is a valuable resource for Warhammer Fantasy Roleplay players and GMs alike, providing new options for martial characters and background on the military of the Empire and the legions of the Ruinous Power Khorne. Players will find several new careers in Omens of War, inspired by the Empire’s militaristic traditions, as well as over 50 new Action cards. The addition of mounted combat rules and horses as a new type of Follower will open new ways to engage your enemies, while new Enhance cards give you more thematic control over your fighting styles.
Game Masters will not only find extensive background on the Blood God Khorne and his legions, they will also discover new ways to challenge their players with Severe Injury rules. These deadly cards are similar to Critical Wounds, however they represent potentially permanent and debilitating wounds that combat in the Old World even more brutal. The Liber Carnagia: The Book of Blood also provides GMs with an all new adventure that will send their players into the thick of battle.
Omens of War comes with two new sourcebooks, over 50 Action cards, 20 Creature cards, 10 Career sheets, and 40 cardboard standups, as well as new Condition, Location, Item, Mutation, Talent, and Severe Injury cards. Additionally, Omens of War also provides all the tokens, handouts, and other materials needed to run the included adventure.