Revenge is a collection of rules specifically written for warfare in the Middle Ages. From the Dark Ages to the rise of gunpowder, war was the sport of nobles who knew that virtue, leadership, and courage were the only principles of war.
Revenge contains three sets of rules each emphasizing a romanticized view of an aspect of medieval battle: Deus Vult is for field battles, Into the Breach for sieges and Sluys for naval warfare.
Deus Vult is designed for 15mm miniatures, each model representing 20 men, but can be easily scaled for use with 25mm miniatures. Meanwhile, Into the Breach is designed for 25mm miniatures representing 5 men each. Sluys is intended for 1:100 scale ship models and 15mm miniatures.
There exists also a supplement, "The Normans", which contains several scenarios for Revenge, but no new rules.