He is identical to Buzz Lightyear in every way, except for having facial hair colored dark blue. He wears armour similar to Zurg's, but with pants and without a cape, and the letter L in the center of his chest instead of the letter Z.
Not much is known about the Evil Buzz Lightyear's past or how he came to be evil in the first place. He is, however, in possession of the forces and staff which formerly belonged to the Zurg in his dimension; and once mentioned that the Zurg in his world didn't have what it took to be evil. This leads us to believe that it was after acquiring Zurg's forces that he went on to conquer his dimension, destroying most planets along with the headquarters of the Galactic Alliance and Star Command.
The Lightyear Factor
One of Zurg's brain pods accidentally creates a rip in the fabric of the universe, leading the Evil Emperor and his forces to an alternate dimension, where planets like Jo-Ad, Tangea, Bathyos and Capital Planet lie in ruin and Star Command is nothing but cosmic dust. Excited at the prospect of meeting his other self, Zurg boards the counterpart dreadnaught, but comes face to face with an evil Buzz Lightyear instead. Quickly shifting gears, he proposes that he and Evil Buzz work together to conquer his dimension, aptly suggesting that there is a worthy enough opponent for him to face there; none other than his own counterpart, Buzz Lightyear. Though at first reluctant to repeat what he had already done, this intrigues him and Evil Buzz agrees to follow Zurg into his dimension.
Evil Buzz and Zurg teamed up to attack Zurg's Star Command, after first stranding Buzz in the other reality on one of Evil Buzz's prison planets. However, Buzz managed to escape and ally himself with the Space Rangers of Evil Buzz's universe, who traveled to his home universe with him. Together, the Space Rangers of both dimensions succeeded in defeating Evil Buzz's forces, and the primary universe Rangers supplied their counterparts with resources that allowed them to retake their home dimension.
Feeling that Buzz had "ruined" his home universe, Evil Buzz decided to return the favor by forming a partnership-both professional and romantic-with Gravitina. Adopting Buzz's old persona of Shiv Katall, he stole various materials needed for a space station in orbit around Capital Planet's sun. This station was positioned so that Gravitina could use her powers to produce devastating sunquakes that would send streaks of molten plasma hurtling around the galaxy. Eventually his true identity and intentions were discovered, and Buzz and Mira Nova confronted him and Gravitina aboard their space station. Evil Buzz showed his true colors by abandoning Gravitina when the station stated to come apart, and seemingly fell into the sun and perished. Unbeknownst to Buzz and the others, however, Evil Buzz managed to survive by clinging to a piece of debris that floated away from the sun.
Essentially a nastier, more consistently evil villain than Zurg. He is also shown to be really uncaring, as he just leaves Gravitina to die.
He possesses excellent fighting skills, weapons training, etc. He also wields a laser gun which can blow up places in one shot, and a jetpack that is identical to the real Buzz's. Overall, he is very much the same as the good ('normal') Buzz.
Role in the series
It's revealed in the Chronicles series that his universe, and any other nega universe, baring exceptions, take place in the same UUniverses where the villains rule over everything. Evil Buzz was a member of Team Nefarious-2 but got lost since his first defeat, and tried to get independent revenge since then until his team came back after the events of The Phineas and Ferb Movie when Doofenshmirtz-2, who is from the same dimension, wanted to repay his kindness, bringing in Doctor Nefarious-2 to aid with their trademark Correctors which could digitally make incompetent villains into competent and superior villains.