|In 130 AC, the riverlands
During the Dance of the Dragons, Adrian took command of the Lannister host after Lord Jason Lannister fell in the Battle at the Red Fork. Thrice repelled by the rivermen, Adrian and a hundred handpicked knights stripped off their heavy armor and swam across the river, upstream of the battle. Adrian then led the knights in circling around to take Lord Tristan Vance's lines in the rear, personally slaying the riverlord. The ranks of the rivermen shattered, allowing the westermen to cross into the riverlands.
The Lannister host continued to march east towards Harrenhal, winning victories under Adrian's command. The westermen were briefly checked at Acorn Hall by Lord Joseth Smallwood and Lord Petyr Piper, but Lord Piper died in battle and Lord Smallwood retreated back to his castle. Three days later, the rivermen regrouped under a hedge knight, Ser Harry Penny, and gave battle to the westermen again. While the Lannister host once again prevailed, Ser Adrian and Ser Harry killed each other in the fighting.