Prime Directive PD20 Modern Core RulebookExplore the Final Frontier! Brilliantly compiled by Jonathan M. Thompson, Prime Directive PD20 Modern allows you to take the heroic role of a starship captain, a commando, a diplomat, a spy, or a trader flying a shuttle of tribbles from planet to planet. Combat on the Klingon border! Intrigue on the Romulan front! Danger on the Tholian boundary! Orion pirates in the trade routes! Logic on the Vulcan homeworld! New Empires: Romulans, Klingons, Gorns,