But he realized someone had taken Gucci sunglasses his mother had given him, and went back to get them. The same people he had tangled with before began mocking him and calling him names, then dragged him into the driveway to beat him up, he wrote. He staggered away in pain.
A 22-year-old neighbor at Capri Apartments in Isla Vista said he saw Rodger come home, crying, "his face all bashed in, his knuckles cut up."
The neighbor, who asked not to be identified, said he had tried to get Rodger to hang out and party with him and others in the communal courtyard. Rodger usually said no, and the few times he agreed, "he just sat in the chair and stared at everyone the entire time."
Seeing Rodger injured, the neighbor asked what happened. Rodger said he was jumped by a group of men.
"I'm going to kill them, and kill myself," the neighbor recalled him saying.
Rodger wrote that he first began to plan his "Day of Retribution" in the spring of 2013. He bought his first gun at "Goleta Gun and Supply," a Glock 34 with $700 he had saved from money given to him by his parents and grandmothers.
"After I picked up the handgun, I brought it back to my room and felt a new sense of power," he wrote. "If only one pretty girl had shown some form of attraction to me, the Day of Retribution would never happen. I'd never even consider it."
He wrote that he next bought a Sig Sauer P226 for $1,100.
As he planned the attack, he left a trail of bitter comments on online forums.
The Southern Poverty Law Center collected a string of racist and misogynistic comments he made on a site called PuaHate.com. In one he ridiculed an Asian man trying to date a white girl, and said it was "rage-inducing" to see a "black guy chilling with 4 hot white girls."
The videos give a more intimate view of his pathos. One afternoon, he was walking through the parking lot of the Sandpiper Golf Club on the bluffs just west of Isla Vista.
"I come here to admire the whole beauty and serenity of the place," he said, affecting a haughty voice. "The world is such a beautiful place. It's such a tragedy that I've had such a pathetic life in it, all because of the cruelty of humanity and women."
He said he went there regularly to watch the sunset because usually there were no couples to envy.
He approached his car, and the camera caught his reflection on it. "There's me, in all my fabulousness," he said with disdain. "Elliot Rodger. I am so awesome."
He sat in the driver's seat.
"Sex, love, companionship — I deserved those things.... But girls are not sexually attracted to me."
His tone turned more menacing.
"That's a problem I'm going to rectify. I, in all my magnificence and power, I will not let this fly."
With a smirking snort, he signed off. "It's an injustice that needs to be dealt with."
Times staff writers Rosanna Xia, Rong-Gong Lin II, Randy Lewis and Mark Olsen in Los Angeles and Stephen Ceasar in Isla Vista, Calif., contributed to this report.