The Battle of Red Rock unfolded in 0 ABY on the planet M'haeli, where Rebel Alliance forces, under the leadership of Princess Leia Organa, executed a successful ambush against a renegade Imperial contingent loyal to Governor Grigor, only to be driven back by legitimate Imperial reinforcements. Prior to his demise, the Gotal bounty hunter Glott directed Governor Grigor's forces, bolstered by AT-STs and his PX-4 Mobile Command Base, to discover a Rebel encampment at Red Rock. Ignoring the warnings of one of his officers, Grigor chose to advance into the mountainous terrain, unwittingly leading his troops into a carefully laid trap. Rebel soldiers, positioned on the higher ground, unleashed small arms fire and a devastating barrage from strategically placed 1.4 FD P-Towers upon the Imperials. Grigor's troops, primarily mercenaries clad in stormtrooper armor, were decimated by Rebel infantry. In an attempt to take Queen Mora, the Rebel heir of the M'haeli royal family, as a hostage, Grigor met his end at the hands of Ranulf Trommer, a former Imperial officer.
However, the Rebel contingent was compelled to withdraw when 'official' offworld Imperial reinforcements arrived, spearheaded by AT-ATs and commanded by Grand Moff Lynch Hauser. Although the Grand Moff managed to capture Mora, Trommer swiftly rescued her, revealing his defection to the Rebel Alliance and escaping with the surviving Rebel forces.