All spoilers regarding the Prequel Trilogy, the Original Trilogy, and The Clone Wars are unmarked. Examples relating to Disney's EU and the new movies can be spoiler-tagged if deemed necessary.
Tropes specifically applying to the characters based on their appearances in Star Wars Legends can be found here.
An assassin droid built to look like a protocol droid and the product of one of Tarkin's research programs. He is later salvaged by Dr. Aphra and placed in Darth Vader's service. Triple-Zero later takes over as the Son-tuul Pride and becomes a criminal kingpin.
- Adorkable: Despite how much of a Sadist he is, his gleeful reaction to horrible things occurring makes him seem like a excited fanboy.
- A.I. Is a Crapshoot: After searching long and hard for his first memories to discover who created him to be the perfect killing machine, he finds out that he was just a defective personality and his creator intended to junk him.
- Arch-Enemy: Grows into this for Chelli Aphra after turning against her.
- Ax-Crazy: Ruthless and sadistic as anything. He is not even truly loyal to Aphra despite his programming forcing him to obey her, and is actively looking for ways to get around it so he can murder her. When Aphra gets knocked out during Vader Down, Triple-Zero pretends to think she is dead so he can ignore his programming and orders BT to open fire with everything he has on the Rebels surrounding her.
- Bad Boss: Regularly tortures and murders his henchmen as the leader of the Son-tuul Pride, and allows them all to be arrested or killed while he escapes Tolvan's raid on his base.
- Beware the Silly Ones: He looks like a regular old protocol droid, with a taste for torture.
- Big Bad: The fourth arc of Dr. Aphra has Triple-Zero become the main villain of the series, having blackmailed Aphra into becoming his operative and forcing her to commit crimes on his behalf, culminating in stealing his original memories from a highly-fortified imperial research facility.
- Big Guy, Little Guy: Triple-Zero is the big guy to BT-1's little guy.
- Bilingual Dialogue: Much of his banter with BT-1.
- Blood Lust: Is convinced that the only reason organics rule the galaxy is because they have blood, and therefore Midi-chlorians. It's left unclear whether his plan to give droids the Force by installing syringes so they can refuel on the battlefield would actually have worked because Vader refuses to let him try.
- Bread, Eggs, Milk, Squick: His introduction sentence amounted to "Hello, I am Triple-Zero and I specialize in protocol, etiquette and torture."
- The Brute: For Vader, alongside BT-1.
- Comedic Sociopathy: His completely nonchalant attitude about torture and murder is Played for Laughs.
- Deadpan Snarker: Yep, and Dr. Aphra lampshades it after he gives her some lip about being sent into an old Geonosian droid factory.
- Despair Event Horizon: After losing BT, being pitied by Aphra, and learning he was just a random mistake rather than the perfect killing machine he's always thought he was, making him no better than the organics he hates, Triple-Zero decides to set off the proximity bomb in his head. It takes BT's reactivation for him to change his mind.
- Even Evil Has Loved Ones: His reactions to BT's death heavily implies that he cared about him on some level, and it's Aphra reactivating BT that convinces him not to destroy himself.
- Even Evil Has Standards: He claims that he won't torture droids. This is complete banthacrap, since he's perfectly willing to kill or maim droids (he'll just turn of their pain receptors first). He simply prefers torturing organics.
- Evil Counterpart: To C-3P0.
- Evil Is Not a Toy: Aphra may have him and Beetee on a leash, but when her conscience (such as it is) starts to get in the way of his bloodthirstiness, he demonstrates just how dangerous it is to leave him the slightest bit of wiggle room when he calls in Darth Vader. He uses Dr. Aphra's fear of Vader to blackmail her into working for him when he becomes a crime lord, and enjoys forcing her on missions with lots of killing.
- Exact Words: When he has his lost arms replaced, the mechanic notices that Triple Zero's request for installed tools includes syringes, and can't help wondering what does a protocoll droid need for them. Triple Zero claims it's for medical emergencies. BT calls him out on lying, but he rejects the notion, on the grounds that he didn't specify whether he meant to solve or create said emergencies.
- Fantastic Racism: Utterly despises biological creatures and believes in the superiority of droids over organic life.
- Faux Affably Evil: His speech pattern is similar to C-3P0 but this droid is very much ruthless and sadistic.Triple-Zero: I have good news and bad news about the gentlemen. Good news: I have great confidence that I have managed to extract all relevant information from *ahem* "Doctor Cylo-IV". I know the location of his research base and the nature of his commission from the Emperor, etcetera, etcetera.
Darth Vader: Then dispose of him.
Triple-Zero: Ah, then I have doubly good news: he's already dead.
- Glowing Mechanical Eyes: Red ones at that.
- Jerkass: A sadistic robot who loves torture and murder.
- Killer Robot: He is an assassin droid after all.
- Kill the Ones You Love: Well, not truly, but he references the trope when he gives the order to kill Aphra, as he truly enjoyed how much chaos, death, and pain she caused and hoped she'd come around to being as unrepentantly evil as he is.Triple-Zero: It's true what they say. Love is murder.
- In Love with Your Carnage: One reason he followed Aphra for so long before betraying her is because of how much fun he had torturing and killing people on her behalf while getting to witness all the chaos she intentionally and unintentionally caused.
- The Man Behind the Man: After breaking free of Aphra's control, Triple-Zero takes over the Son-tuul Pride with Yonak as his figurehead.
- Omniglot: He can still serve as a protocol droid if the need arises.
- Really 700 Years Old: The personality matrix that drives Triple-Zero is in fact centuries old. It was temporarily taken out of quarantine by the Tarkin Initiative in an attempt to control it, but it broke free and went on a three-year long murderous rampage before being recaptured and put back into quarantine.
- Red and Black and Evil All Over: He has black plating with glowing red eyes.
- Red Eyes, Take Warning: Triple-Zero has red lenses, as shown in his page image.
- Ridiculously Human Robot: In the same vein as C-3P0.
- Robotic Psychopath: Let's put it this way, he tries to kill Dr. Aphra soon after she reactivates him for no reason but force of habit. Evazan outright says Triple-Zero is the closest thing he's ever seen to "programmed evil." Although it turns out he wasn't programmed that way, he's just defective.Dr. Aphra: This is the Triple-Zero protocol personality matrix. Had a few bugs. Twitchy coupling. Neurocybernetic glitches. Tendency to drain organics to collect their blood. That kind of thing.
- Sadist: See Torture Technician below.
- Sore Loser: Has a great love of dejarik, but because most of his non-essential programmed skills have been removed to make room for torture protocols, he's absolutely awful at it — and doesn't take kindly to losing. When trying to prove he's a "good sport" to a bar patron mocking him, he offers out a deathly electrified hand to shake.
- Servile Snarker: His programming means he has to serve Aphra and obey her commands. It doesn't mean he has to be polite about it.
- Species Loyalty: He enjoys torturing and killing organics but is horrified at the destruction of droids. He refuses to torture them himself. However, he has no problem destroying a droid after turning off their pain receptors.
- Those Two Bad Guys: He and BT-1.
- Torture Technician: One of his other specialties besides assassination and protocol. And he very much enjoys this line of work.
- Tranquil Fury: The start of the fifth Dr. Aphra arc, Broken Inside, has Triple-Zero calmly massacre an entire spaceport while repeating Aphra's name over and over due to her encrypting his original memories. His attempt to claim to BT-1 that he is not angry is... unconvincing.0-0-0: Angry? Oh, goodness — no! So she put an unbreakable encryption on my most precious memories and vanished. Worst things happen on Kessel, as they say. I imagine I shall simply make some polite inquires. Take some... calm and measured steps. But angry? Bless your circuits. No, you know me Beetee. I don't get angry.
An assassin droid built to look like a astromech droid and the product of one of Tarkin's research programs. He is later salvaged by Dr. Aphra and placed in Darth Vader's service.
- Big Guy, Little Guy: The little guy to Triple Zero's big guy.
- Evil Counterpart: To R2-D2. And to Chopper of Rebels fame, a similarly violent astromech with a mean streak but technically a good guy.
- Kill It with Fire: BT-1 has a flamethrower, and he likes using it.
- Killer Rabbit: Despite his harmless appearance, he is one of the nastiest droids out there and is feared throughout the Empire.
- Killer Robot: He is an assassin droid after all.
- More Dakka: Let's put it this way, he has the firepower to take out a Clone Wars droid battalion in a couple of seconds.
- Morality Chain: While they're both evil, BT is able to reign in Triple Zero's more destructive instincts. In the final issue of Worst Among Equals, him being restored by Aphra not only keeps Triple Zero from destroying himself, it later makes him hesitate to kill Aphra later, when he has a clear opportunity to do so.
- Off-Model: Despite being introduced with a specific and unique head, he is sometimes illustrated with an R5 head or a Legends continuity R6 head. Toys of BT often give him the same head shape as R5 droids.
- Self-Made Orphan: Soon after he was activated, he destroyed the research station and the team of scientists and engineers that created him.
- Shout-Out: His missile launcher and gatling gun are specific references to the Marvel character War Machine.
- Those Two Bad Guys: He and Triple-Zero.
- Too Dumb to Live: His unrestrained bloodlust leads to him trying to kills Darth Vader in the fifth arc of Doctor Aphra. Vader cuts him in half with one strike.
- Walking Armory: The amount of firepower he carries within his chassis is impressive.
- We Can Rebuild Him: After being cut down by Vader, he is rebuilt and works with Tam Posla to hunt down Aphra and Triple-Zero.
The son of the previous leader of the Son-tuul Pride. Yonak is among the criminals who attempts to acquire the Rur crystal from Dr. Aphra at her auction.
- Cyborg: His right eye is a cybernetic replacement.
- Enemy Mine: Combines his bid for the Rur crystal with Sutha, who was the Hutt clan's primary agent in taking down Yonak's father. That being said, he plans on betraying the Hutts should their bid win. They continue their partnership in a bid to escape when Rur acquires a droid body and begins wrecking havoc across the station.
- Even Evil Has Loved Ones: He loved his father, and despises the Hutts for having helped the Empire kill him.
- Puppet King: Triple-Zero and Beetee take over the Son-tuul Pride after escaping the Rur action with Yonak, turning him into little more than a terrified figurehead for the homicidal droids as they expand their criminal empire.
- Single Tear: Sheds one after Triple-Zero and Beetee make him watch as they use him as bait to kill his own men, who are trying to confront him in under the mistake that he betrayed them only to learn that the two droids set them up.
- What Happened to the Mouse?: He does not appear at all in fourth arc of Dr. Aphra, despite its heavy focus on the Son-tuul Pride and Yonak becoming a figurehead for Triple-Zero.
Species: Human (cyborg)
A cyborg enforcer working for the Son-tuul Pride.
- Bald Woman: Can't really be helped, she has the AJ^6 cyborg construct on her head, which needs a clean-shaven head to be attached.
- Blush Stickers: She has one dot on each of her cheek.
- Cyborg: The AJ^6 increases her intelligence and provides a direct link to Triple-Zero, including a holotransmitter on the top of her head.
- Gatling Good: Her weapon of choice.
- He Knows Too Much: Aphra kills her to protect Tolvan.
- Jerkass: She shares her boss' brutality and enjoys tormenting Aphra.
- Killed Offscreen: By Aphra when Rexa catches her with Tolvan.
- Machine Monotone: Comic-book equivalent. Her speech bubbles are squares and their font italicized.
- Non-Standard Character Design: Her taste in fashion is rather foreign to the standard in Star Wars.
- The Stoic: If she says anything funny, it's a snarky comment. Probably because of the cyborg construct on her head.
- Straight Man: To Aphra's Loveable Rogue.