Trench was a Harch admiral and naval commander who survived a number of presumed deaths throughout his career. Hailing from Secundus Ando, he acquitted himself in engagements with the Galactic Republic, all the while savoring the terror he struck in his enemies. Years after his purported death at the Battle of Malastare Narrows, he resurfaced during the Clone Wars, becoming a key officer in the navy of the Confederacy of Independent Systems. From the dreadnought Invincible he oversaw the Confederate blockade of Christophsis, which brought him into conflict with a Republic battle group led by Jedi Generals Obi-Wan Kenobi and Anakin Skywalker along with an old foe, Admiral Wullf Yularen. When Skywalker and Yularen attempted to use an experimental stealth ship to breach the blockade, Trench began a deadly game of cat and mouse with them. Though Skywalker outwitted him by redirecting a volley of tracking torpedoes at the Invincible, Trench managed to survive his flagship‘s demise.

During the Battle of Ringo Vinda, Trench captured clone trooper Tup—who had mysteriously gunned down Jedi General Tiplar—and tried to send the clone to Separatist leader Count Dooku for examination, though a Republic team intervened and rescued Tup. In the Battle of Anaxes, Trench besieged the Republic shipyards at Anaxes for weeks on end, exploiting the Techno Union‘s secret access to a Republic strategy algorithm. Even as the tide of battle began to turn, Trench remained intent on annihilating the Jedi and their clone infantry. Though he activated a bomb beneath the assembly complex on Anaxes, Skywalker infiltrated Trench’s flagship and forced the admiral to divulge the sequence to disarm the device. When Trench tried to retaliate, Skywalker drove his lightsaber through his chest, inflicting a death that even the hardened Harch could not escape.