Rick Hunter, the RDF, and new mecha troops have merged to create the Robotech Expeditionary Force (REF). Their goal, to confront the Robotech Masters in the SDF-3 and stop the insane battle that threatens both worlds. The Earth champions join forces with aliens and unlikely allies of all kind to fight the invid who threaten to enslave or destroy entire galaxies. The Sentinels is based on the plots, conceptual art and models sheets for the never completed and little seen Robotech II: The Sentinels animated television series. The Sentinels RPG and the REF Field Guide are the only definitive reference books for Robotech II: The Sentinels currently in print anywhere! Both books are filled with great artwork and never before seen illustrations, side views and cut-aways. A must for Robotech fans and collectors of all kind!