The only creature who could ever make Data truly feel something was his twin brother, the evil, Borg-diddling Lore. Science fiction is full of nemeses, heroes and villains whose most fearsome foes live right in their immediate families. We delved into the deep psychology of science fiction’s most bitter sibling rivalries and now we know who is (or should be) mom and dad’s favorite.Data vs. Lore: When Data discovers the disassembled body of big brother Lore on Omicron Theta, it seems that our navel-gazing android friend is no longer alone in the universe. But Lore turns out to be a bit of jerk, mocking Data’s lack of emotions, experimenting on former Borg drones, and trying to feed the Enterprise’s crew to the crystalline entity. Advantage: Data Lore might be more fun at parties, but his lack of ethics earns him few friends and an incapacitating phaser beam to the chest. Thaddeus “Rusty” Venture vs. Jonas Venture, Jr.: Despite being twins and fellow super-scientists, the elder Venture brothers have very little in common. Rusty is a lanky, bald neurotic who has as much trouble with his super-science business as he does with the ladies. Self-confident and short-statured J.J. has a full head of hair, a steady relationship with Sally Impossible, and a constant stream of government contract work. Consequently, Rusty rues the day the doctors removed his parasitic twin from his body. Although, if fan speculation about one character is correct, Rusty may find that J.J. isn’t his most obnoxious brother. Advantage: J.J. Jonas Jr. is so far ahead of the game that he isn’t even aware they have a rivalry.

Bender vs. Flexo: Despite the mirror universe goatee, Flexo isn’t a bad guy. Fortunately, Bender’s got enough evil for the both of them. He uses his resemblance to Flexo to frame Flexo for various crimes and starts dating Flexo’s ex, Anglelyne. But he can’t get over the nagging feeling that she may still be in love with Flexo. Advantage: Bender Bender’s actions land Flexo in prison and get him smashed beneath an unbendable girder. Sure, Bender’s insecurities get Flexo the girl, but, let’s face it, Bender would have dumped her for the next busty fembot who glanced his way. Ender and Valentine Wiggin vs. Peter Wiggin: Peter Wiggin always resented his younger siblings, Ender for his messianic status and both Ender and Valentine for their exclusively close relationship. Peter terrorizes Ender until the latter leaves for Battle School and manipulates Valentine into aiding him in his political ambitions. Advantage: Draw Although Ender and Valentine do sail into the hyperspace sunset together, Peter gets his wish to become leader of the free world. He and Ender even get lovey-dovey towards the end of Peter’s life, with Peter apologizing for all he did and Ender penning Peter’s novel-length eulogy.

Professor Xavier vs. Juggernaut: With a name like Cain Marko, Charles Xavier’s stepbrother was destined for brother on brother violence. Enduring years of abuse and his father’s apparent favoritism of Charles, Cain turned his anger on the one person he could: Charles. And years later, when the temple of Cyttorak comes crashing down on their heads, Charles escapes, unwittingly leaving Cain to spend years digging himself out. It’s no wonder there’s bad blood between the pair. Advantage: Professor X Despite repeated efforts, the Juggernaut was never able to exact revenge on Xavier, always thwarted by the X-Men. And Charles later proved to be the bigger man (although not literally), welcoming Cain into his home and onto his team. At least the Juggernaut came away with a better catchphrase.

Jaina Solo vs. Jacen Solo: Force-sensitive wonder twins Jaina and Jacen are happily close playmates during their childhood, despite their diverging interests. But when Jacen turns to the Dark Side and kills Jaina’s mentor, it puts a damper on their relationship. Advantage: Jacen Sure, Jacen becomes the evil Darth Caedus, and Jaina bests him in personal combat. But he also possesses a more thorough understanding of the Force than his sister and ultimately sacrifices his soul to prevent the galaxy from dissolving into chaos. Paul Atreides vs. Alia Atreides: At the end of Dune Messiah, Paul Atreides goes into exile, leaving his sister Alia as regent of the Fremen people. But when Paul returns, he finds that Alia, now possessed by the memory of their ruthless grandfather Baron Vladimir Harkonnen, has helped corrupt his religious teachings, and begins preaching against her. Advantage: Paul Alia/Vladimir has the upper hand momentarily when her priests stab Paul to death. But the return of Paul’s children prompts Alia to regain control of her body and end her life, ensuring Paul’s legacy among the Fremen.

Austin Powers vs. Dr. Evil: Austin Powers devotes his life to battling the nefarious (though incompetent) Dr. Evil, even sacrificing his time in the swinging 1960s so he can enter cryofreeze and live to fight Evil another day. Despite a strong family resemblance, it takes Powers three movies to find out that Dr. Evil is, in fact, his twin brother.

Advantage: Dr. Evil After being repeated thwarted by Powers, Dr. Evil reconciles with his family and gets to save the day. Plus, thanks to all those companies that were bankrolling his evil schemes, he’s rich. And if he ever feels the need to stick it to Powers again, he can always tap his son Scott, who has taken up evil mantle. Barry Allen vs. Malcom Thawne: Malcolm Thawne always thought he was the son of a pair of con artists. But, after seeing his identical twin Barry “The Flash” Allen on the street, he learns the truth. Furious with Allen for living the life that was rightfully his, Thawne becomes Cobalt Blue and vows to take his revenge on his Allen and his descendents. Advantage: Barry Allen After all the time he spent obsessing over Allen, Thawne faces him only twice in a thousand years. He did manage to kill Allen the second time, but a time-traveling Wally West manages to undo the act.

KITT vs. KARR: Knight Rider’s prototypical vehicle, the flawed KARR was placed in storage after the creation of KITT. After it’s reactivated, it hopes to stay that way, but KITT and Michael chase it down and cause it drive into the ocean. After that, it’s out for blood. Advantage: KITT KARR faced off against KITT twice and twice lost, with the second encounter resulting in KARR’s destruction. But last we saw his CPU, the LED was still flickering, leaving room for future revenge.

Martin Swinton vs. David: AI finds young Martin Swinton in suspended animation due to an incurable disease. Mecha David proves a godsend for Martin’s grieving mother, but once Martin is cured and returns home, he is unhappy to find that the robot has taken his place. Martin’s behavior turns eerily psychopathic and he causes David to nearly drown. Advantage: Martin Since Martin is bent on killing David and there are laws against abandoning one’s fleshy children, the Swinton parents send the naïve and utterly devoted David off into the world. He outlives them all, but all he wanted was to go home to mom.

Niki Sanders vs. Jessica Sanders: Peter and Sylar have their own issues to work out, granted, but Niki and Jessica have to deal with the fundamental challenge of who controls their body. Do we lie to DL? Do we murder those FBI agents? Do we have sex with that congressional candidate? Advantage: Niki In the first season, it’s Jessica who calls the shots. By the second season, Niki has employed Mohinder Suresh to suppress Jesssica and her extraordinary abilities, but at the price of her health. Vincent Freeman vs. Anton Freeman: In the DNA-obsessed world of Gattaca naturally conceived Vincent passes himself off as a member of the genetic elite while his genetically engineered brother Anton attempts to solve a murder in Vincent’s office. The pair’s rivalry serves as a metaphor for the film’s commentary on nurture versus nature. Advantage: Vincent Anton solves his case, Vincent is never found out, and the two settle the question of superiority with a swimming match. Vincent bests his brother, proving that perseverance can triumph over genetics. Tima vs. Rock: In the anime Metropolis, Duke Red adopts the orphan rock after the death of his daughter Tima. But when a robot version of Tima is created, Duke Red ignores Rock in favor of the double, even promising her the throne. Rock decides the only way to earn back his father’s love is to destroy the robot Tima. Advantage: Neither Rock fails to kill Tima or regain his father’s attentions, and Tima comes to learn that she was create to become a weapon. And the actions of Duke Red has tragic results for both siblings.

Godzilla vs. SpaceGodzilla: Godzilla’s clone from space, SpaceGodzilla lands on Earth and imprisons Little Godzilla in a crystalline prison, and proceeds, as giant monsters do, to destroy a nearby city, defeating the robot MOGUERA and creating a fortress made of giant crystals. Advantage: Godzilla Godzilla finishes SpaceGodzilla off with his Red Spiral Atomic Breath, frees Little Godzilla, and heads on home.