Grand Admiral Thrawn
The highest-ranking nonhuman officer within the Imperial Navy, and the first great enemy of the New Republic. Thrawn rose to power during the Emperors reign and managed to organize the remnants of the Imperial fleet shortly after the Battle of Endor. Refusing to recognize the New Republic, he launched a campaign of terror to reclaim the universe for the Empire. Although he was eventually defeated by the heroes of the New Republic and their allies, his efforts revitalized the Empire, ensuring that it would remain a threat for years to come.
A blue-skinned, gaunt humanoid with red eyes and a regal bearing, Grand Admiral Thrawn was the first alien to be appointed to a position as one of the 12 Grand Admirals of the Empire. He spent much of the Galactic Civil War conquering the Unknown Regions on the fringes of the galaxy, and did not return to the Galactic Core until a full five years after the Battle of Endor. When he discovered that the Emperor had been killed, he began to rally the remaining Imperial forces for a strike on the New Republic. His exploits and his ultimate failure are thoroughly chronicled in Heir to the Empire, Dark Force Rising, and The Last Command.
Thrawns plot to overthrow the New Republic had several components. First, he discovered that the rodentlike creatures known as ysalamiri were capable of dampening a Jedis connection to the Force. After collecting a number of the beasts from the planet Myrkr, Thrawn managed to neutralize Luke Skywalkers powerful abilities. Thrawn also uncovered the Emperors cache of experimental devices, including a cloaking mechanism that he used to great effect in his conflict with the New Republic. Finally, Thrawn allied himself with Joruus Cbaoth, an insane Dark Jedi clone who plotted to convert Princess Leias unborn twins to the dark side and later attempted to kidnap Luke.
Thrawns greatest weapon may have been his horde of deadly Noghri. Long before the Battle of Endor, Darth Vader had tricked the vicious Noghri into swearing allegiance to the Empire. Emperor Palpatine subsequently molded the species into a secret death squad. Under Thrawns control the Noghri were used for covert strikes against New Republic leaders, including Princess Leia. Thrawn also employed a Noghri named Rukh as his personal bodyguard. When the Noghri were assigned to capture Leia, however, they recognized her as Darth Vaders daughter. She then convinced the Noghri that Vader had betrayed their people. They secretly joined forces with the New Republic.
For the next several months, Thrawn plagued the heroes of the New Republic. He stole mole miners from Lando Calrissian, captured a large contingent of Katana dreadnaughts, and hounded Leia and Luke across the stars. He finally launched an assault on Coruscant, but he was routed by a fleet of smugglers. Soon after this defeat, Thrawn was finally confronted by his bodyguard. Seeking to avenge the Empires deception of his people, Rukh plunged a dagger into the Grand Admirals heart.
Ten years after Thrawns alleged death, the New Republic began uncovering rumors of the Grand Admirals survival. As recounted in Specter of the Past and Vision of the Future, the full effect of Thrawns reported return has yet to be seen, but it will surely threaten the future of the New Republic.