Formerly known as Sergeant Oak, the newly minted 21 year-old Staff Sergeant Rusty Oak from Chandrila was one of the 15 Imperial Navy Trooper survivors (of 32 Navy Troopers and 6 Scout Troopers total) on a communications & sensor listening post deployed by the Darkest Night to the Sentry Moon during operations conducted by the 115th Naval Battle Group during The Battle for Lepsawn 1-9 (2 BBY). The temporary outpost was attacked on the moon by natives on the forest moon being controlled by mercenaries running a spice operation for the Circle Crime Family, as well as the mercenaries attempting to activate a long dead planet killer weapon housed in an secretive abandoned base dating back to The Great Lepsawn Civil War (47 BBY to 37 BBY). The weapon, and another one similar to it found on Lepsawn 1-9 by the Circle Crime Family, was to be used to destroy the Darkest Night and her supporting ships of North Squadron during The Battle for Lepsawn 1-9.
After being rescued by Imperial reinforcements lead by Chief of Security Cain Shinzon (of the Darkest Night), Sergeant Oak (the highest ranked surviving NCO from the listening post), the Security Chief, and several other Imperial Navy Troopers deployed to find missing Imperials during the attack (that they later found dead). In their search, the Imperials came upon the mercenaries' main operation in restarting the planet killing weapon, but never the rumored spice operation. Cain lead an attack on the base that resulted in the deaths of the rest of the Imperial Navy Troopers under his command for the missing Imperials, save for Sergeant Oak and another Navy Trooper. Despite the losses, the mercenaries' operation to restart the super weapon failed and the Imperial mission was seen as a success.
Despite surviving a enemy attack that wiped out most of the initial listening post, leading the remnants of the outpost until reinforcements arrived, and conducting a counter rescue and later assault mission on the mercenaries, Chief of Security failed to recognize Sergeant Oak for anything above and beyond the call of duty. Any praise the Chief of Security gave was minimal at best, as he sought to improve the Sergeant as a man and as a soldier for the greater good of the Empire, instead of reaping praise on Oak for "doing his job". Despite the successes and Cain's strict leadership, Sergeant Oak is very clearly suffering from some form of Shell Shock, Combat Stress Reaction, Posttraumatic Stress Disorder, or combination of the three and his obsession to please Cain to gain approval borders on the line of crazy. Despite his desire to prove Cain wrong---or right---about his abilities as a loyal & skilled Imperial Navy Trooper for the Imperial Navy, Staff Sergeant Oak has masked his shell shock, CSR, and/or PTSD well and has been recognized by the new Chief of Security aboard the Darkest Night, Gotz Richter, for both his past accomplishments on the Sentry Moon and has been rewarded not only a promotion to Staff Sergeant, but also the Crimson Star.
To date, Staff Sergeant Oak has taken his shell shock and crazy obsession with Cain to become a loyal and deadly Imperial Navy Trooper. At the moment, his skillset and mindset is limitless; but that limitless may come with a heavy cost later. Only time will tell.