Biggs and Janek, nicknamed Tank because of his drinking habits, talked a big game about leaving the planet in time and signing up for the "academy". They let Luke and the others believe this was the Imperial Academy, what they were actually hoping to get accepted into was the Prefsbelt Psychiatric Academy. Yes, the premiere psych school in the Galaxy. Though both were accepted, Biggs quickly grew tired of the exams and techno babble. He just wanted to get some peeps on a couch and help them sift through their issues.
Biggs quickly formed a friendship with Derek "Hobbie" Klivian, a fellow Psych school slacker. Klivian was also extremely bored with the routine at the Academy, and eventually showed Biggs a leaflet he'd found advertizing the Rebel Alliance. Adventure! Excitement! These were the things you'd find in the Rebellion. It sounded promising.
Darklighter and Klivian met with Tenb Mumn, the Rebel recruiter, and were told about the elaborate yet brief Psychology program the Rebellion offered. It sounded completely perfect, and they signed right up.
Of course once they reached Sullust they learned there was absolutely no psych program offered at all. They'd been tricked, and were forced into the pilot program by Jan Dodonna, who told them pilots were constantly getting killed fighting the Empire and they would basically throw anybody into an X-Wing anymore. Biggs didn't like the sound of that, but the controls weren't too dissimilar to his old T-16 back home.
Biggs was sent off to Yavin IV with Dodonna to prep for an assault on the Empire's new Death Star, some planet exploding space station. In the hangar Biggs was shocked to see his old friend Luke Skywalker running around with some hot piece of tail. Biggs ran over, excited to see his little buddy finally got out from under his uncle's sweaty armpit. Biggs of course still couldn't let Luke know about the psych academy, so he played up what a gruff pilot he'd become fighting for the Alliance. Instead of getting into it with Luke, Biggs said they'd talk all about that stuff after the Battle. That talk would never happen.Biggs flew alright during the Battle Of Yavin, with R2-Q2 as his Astromech. However, Darklighter kept ditching Luke to go hide his X-Wing behind Wedge Antilles. This tactic worked until Luke adopted it in the trench of the Death Star, and Darth Vader shot Darklighter's ship up.