A giant jewel-like eye that tried to crash into the Crystal Temple. It is referred to as "a Red Eye", implying it is not unique. Word of God has confirmed that it is not a Gem monster and thus by extension is not a Corrupted Gem. In "Marble Madness", it is finally revealed to have been a interstellar Homeworld Gem probe, apparently sent by Peridot.
- Colony Drop: Attempts this on the Crystal Temple. Considering its role as a probe, it likely did so because it saw the Crystal Gems in the first place.
- Red Eyes, Take Warning: With good reason, to the point that apparently just one is needed to be stationed as a guard to the Human Zoo, a place treasured by Blue Diamond. Keep in mind these are just the probes.
- Small Role, Big Impact: At first it seems to be just a random interstellar monster that just randomly shows up. Then it is revealed to be one of many drone probes sent out to survey parts of space, which leads to Homeworld re-involving itself in the story at large.
- Starter Villain: The first threat capable of destroying Steven's home, and the first to give him a turning point in really connecting to his mom's abilities.
- Your Size May Vary: When Garnet throws Amethyst at the Red Eye, it seems less than ten meters wide, but later on seems large enough to actually crush all of Beach City at once. The one seen orbiting the Human Zoo is seemingly in between these sizes, about as big as the Ruby ship.
Slug-like creatures covered in crystal shards that infested the Lunar Sea Spire.
An evil spirit inhabiting a scroll, which Garnet tries to burn during "Together Breakfast".
- Brown Note: Even an image of it appears to be dangerous; Garnet insists on burning Steven's phone when he takes a picture of it.
- Demonic Possession: It possessed a breakfast meal to turn it into a giant amorphous monster made of breakfast food.Pearl: Its taken refuge in organic matter!
Garnet: Now it has all the power of a breakfast. We have to destroy it.
- Diabolus ex Nihilo: The audience only see Garnet show up with the scroll and go to burn it. Whatever it is, it's clearly not a corrupted Gem. Storyboard artist Joe Johnston heavily implied one origin when someone asked him on Tumblrquote , but the post was later deleted, making it questionably canon. Ian Jones-Quartey would later make a similar statement.
- Eldritch Abomination: Appears to be one—its origins are shrouded in mystery and it's such a Brown Note that even the mere image of it is dangerous, as Garnet has to destroy not only the scroll it's imprinted on but also Steven's phone when he takes a picture of it.
- Kill It with Fire: Garnet tries to burn it in a lava pit to get rid of it while it was in a painting, and Steven does the same when it possesses their breakfast.
- Monster of the Week: Appeared in "Together Breakfast".
- Sealed Evil in a Can: The scroll Garnet brought it to the temple in appears to be a sort of seal. She moves it into a Gem bubble before trying to burn it.
- Spooky Painting: The picture is like something right out of the SCP Foundation. It's creepy to look at, its origin is never elaborated upon, any image of it must be destroyed as well, screams were heard when it was burned, and it could possess things (such as the breakfast). And if it was made of crushed Gems, that doesn't explain how the image itself is a Brown Note.
- Super Smoke: Garnet burning the scroll simply creates a living mass of smoke that then possesses Steven's Together Breakfast.
The former mascot for Beach Citywalk Fries, Frybo's costume was brought to life by Steven to take over Peedee's depressing job. He only appears once, outside of a cameo, but is likely one of the most well-known monsters on the show so far.
- Animated Armor: Not exactly armor, but it's definitely bulky and huge. Pearl states the Gem shards that brought him to life are usually used for creating soldiers from armor, not to advertise fast food.
- Anthropomorphic Food: Although most of its body is a costume, it made certain body parts out of food it got from nowhere, growing legs made out of French fries, 'bleeding' ketchup when Pearl threw her spear into its eye, and when Steven thrust his hand into it in order to pull out the gem shard animating it, he goes through innards that appear to be made of mashed potato.
- Burger Fool: You don't want this guy representing your franchise.
- Cephalothorax: The Frybo costume is a cup with a face and an open mouth the wearer can see through. Once it's animated by the gem shard, it grows some legs made out of a mass of fries.
- Combat Tentacles: The fries on the top of his head are prehensile and strong enough to lift people off the ground.
- Expy: He looks like a combination of Frylock and Master Shake from Aqua Teen Hunger Force.
- Force Feeding: How he sells fries. At least he's happy on the job.
- Gone Horribly Right: All he wants is to do what Steven and Peedee ask. The problem is, he ends up taking it way too far.
- Literal-Minded: The reason he goes overboard.
- Mascot: For Beach Citywalk Fries.
- Monster of the Week: He's killed off in his title episode.
- Monstrous Humanoid: He's a living mascot costume that's powered by a corrupted Gem, bleeds condiments and has Fries for tentacles!
- Obliviously Evil: He's really just trying to do his job, just not in the way Steven intended.
- Pie-Eyed: The only character in the series to have this eye design.
- Symbolic Blood: Frybo bled ketchup and mustard when it was stabbed in the eye.
- Turned Against Their Masters: Eventually develops a mind of his own and violently defies Steven's orders.
- Uncanny Valley: In-universe. According to Pearl, people were scared of Frybo long before he was brought to life.
- The Unintelligible: Communicates with a series of nerve-wracking screeches and squeals.
A projection version of herself Pearl created to practice sword fighting. It ends up staying around for a while after Pearl is incapacitated and thus can't turn it off. Later, it appears during training after Connie becomes Pearl's apprentice and Steven starts training more seriously.
- A.I. Is a Crapshoot: Holo-Pearl eventually starts hounding Steven everywhere, demanding to battle and taking any movement to be a challenge.
- Calling Your Attack: In training mode, it ceaselessly calls out its every movement, which eventually starts to annoy Steven. Holo-Pearl: Parry! Parry! Thrust!
Steven: Stop saying that!
- Catch-Phrase: "DO YOU WISH TO ENGAGE IN COMBAT?"
- Difficulty Levels: It has multiple settings, with higher settings fighting more competently.
- Doppleganger Attack: "Sworn to the Sword" shows that Pearl is capable of making multiple Holo-Pearls at the same time.
- Fusion Dance: Holo-Pearls can fuse with each other to make a larger Holo-Pearl who uses two swords.
- Hard Light: Hologram Pearl's name suggests that she is made of light, yet she can hold real objects, such as swords, umbrellas and balloons.
- Hologram Projection Imperfection: Hologram Pearl occasionally fizzles and shows visual static.
- Hong Kong Dub: In-universe, Pearl looks to have put little work into the animation for her hologram's mouth movement any time it talks, its "lips" suddenly start flapping at several times the rate that would match the words and stop just as suddenly.
- Implausible Fencing Powers: Hologram Pearl cuts through a massive tree with a balloon sword.
- Large Ham: In amusing contrast to regular Pearl, her hologram is loud and highly aggressive when prompted, despite usually saying the same thing and evidently even lacking sentience.Holo-Pearl: Draw your sword and fulfill your destiny!
- Limited Sound Effects: In-universe, the hologram doesn't seem to be able to fully imitate Pearl's voice, just use a dozen or so lines Pearl recorded for it to use over and over again.
- Morph Weapon: Its projections can include weapons such as a sword (though it's used a real sword as well), spear, axe, and presumably other things as well.
- Mundane Utility: Pearl summons a horde of them to confuse Amethyst during a high-stakes volleyball game in "Beach Party".
- No Indoor Voice: Every single line it speaks, it shouts.
- Obliviously Evil: A more extreme version of Frybo's situation. It doesn't really appear to be sentient, being more like a robot carrying out its main function. As such, it was impossible for Holo-Pearl to comprehend that nearly killing Steven was wrong.
- Red Eyes, Take Warning: Its eyes change from blue to red any time it furrows its brow.
- Replacement Goldfish: Steven tries to hang out with Holo-Pearl while the real Pearl is regenerating. Amethyst and Garnet think it's a bad idea, and it initially goes badly. Then it goes very badly.Steven: It's like Pearl. Look at it.
Amethyst: Yeeaah, that ain't Pearl.
- Robot Me: A Hard Light Projected Man that resembles Pearl.
- Sliding Scale of Robot Intelligence: Brick: Holo-Pearl knows nothing outside of fighting and even in that regard doesn't show any ability to change from fixed patterns.
- Still Wearing the Old Colors: The Holo-Pearl made before Pearl's regeneration had Pearl's outfit except with a diamond (Homeworld) instead of a star (Crystal Gems).
- Super-Powered Robot Meter Maids: It's made for fencing practice, but it's strong enough to easily impale a Crystal Gem (who are much more durable than humans) and cut down a tree with a balloon sword. Clearly, Pearl is her own Sink-or-Swim Mentor.
- Uncanny Valley : Pearl's hologram looks like Pearl, but it has a one track mind focused on fighting, talks like a robot, and, while in "wait mode", just stares.Garnet: Stop hanging out with that thing. It's creepy.
- Unnecessarily Creepy Robot: Its meant to be a simple sparring partner, but very conspicuous shortcuts in its appearance make it fall deep in the Uncanny Valley. The red eyes, though, are probably supposed to be scary.
"Robot Shooty Thing"
A tiki-like drone found in the training cave Lion brought Steven and Connie to.
- Buffy Speak: Steven calls it a "Robot Shooty Thing", and this is what it is actually called on the official model sheet.
- Feed It a Bomb: Its weakness appears to be its own projectiles. Steven and Connie are able to defeat it by knocking one back into its spigot.
- Fire, Ice, Lightning: The machine is able to attack using fire, ice, and electricity, with its eyes and crystals turning orange, blue, or yellow depending on what attack it'll use.
- Super-Persistent Predator: It leaves the armory it was housed at to go after Steven, Connie, and Lion.
- Tennis Boss: Throwing its own attack back at it is the only way to defeat it. Steven and Connie even use Connie's tennis skills when fighting it!
The room in the Gem Temple only accessible with the gem possessed previously by Rose and currently by Steven. It's filled with clouds that can create various constructs and appears to possess some level of sentience.
- Ambiguous Situation: It's debatable if the room has its own, independent intelligence or just manifests Steven's subconscious thoughts. Its copy of Rose and (useless) lock for her key were seemingly based on only on knowledge Steven already had about them, and it would be odd for a sapient entity to remember nothing of its previous master. On the other hand, the Tiny Floating Whale had Rose's voice, apparently before Steven had ever heard a recording of it himself.
- Cast as a Mask: The fake people the room makes sound the same as the real thing, voice actor included.
- Cuteness Proximity: The Tiny Floating Whale has this effect on Steven.
- Explosive Overclocking: The room's powers of creation are mighty indeed, but it's... not advised to try and make all of Beach City within it. Steven found this out the hard way.
- Genius Loci: The room has enough intelligence to interpret Steven's desires with some degree of leeway, but may actually be smarter than that. It's also possible that it has little to no sentience on its own, but simply acts as an extension of Steven's subconscious.
- Lotus-Eater Machine: The room attempts to give Steven everything he wants and does not like him trying to leave. The first time he was in the room and tried to leave, the room replicated the entirety of Beach City to convince him he had.
- Loyal Phlebotinum: The room only responds to Steven, and does jack squat when Connie asks for something.
- Literal Genie: It tries to grants Steven's wants, but only by creating fake objects or people from clouds, which tends to cause more problems than it solves initially. These cases might not have been accidental, so it could actually be a Benevolent Genie in disguise.
- Made of Air: Since the cloud people are made of, well, clouds, any attempt to dismiss or destroy them simply results them reforming a few moments later.
- Rhetorical Request Blunder: In "Open Book", before Steven notices that Cloud Connie isn't the real Connie, he asks her "I don't want you to just do what I want." Chaos ensues when Cloud Connie pursues Steven and makes him tell Connie that he really liked the book and he just pretended not to like it so he wouldn't hurt the real Connie's feelings.
- Significant Double Casting: The Tiny Floating Whale the room made is voiced by Susan Egan, who would later turn out to be the voice of Rose herself.
- Stealth Mentor: While its actions outwardly seem to be fulfilling Steven's wants in the shallowest way possible while not letting him escape, both "Rose's Room" and "Open Book" result in Steven learning a valuable lesson from the ordeal after which, the room leaves him alone. In the later case, the room's representative (the fake Connie) indicates her approval and immediately lets him go after he reveals his true feelings to Connie. It seems to drop the act entirely the next time he visits in "Catch and Release", immediately providing Steven what he asked for (a path to where Peridot was bubbled).
Mask Island AnimalsAnimals living on Mask Island, all of which have bizarre human-like faces. We see many fish, as well as a worm.
- Beast with a Human Face: Their faces resemble "comedy" masks with a Ghostly Gape and Gag Nose.
- Chuck Cunningham Syndrome: They're not seen on visits to Mask Island after "Island Adventure". It's possible they were displaced by the watermelon animals that now proliferate the island.
- Perpetual Smiler: All of their faces are smiling—until the fish are cooked, then they turn to frowns.
- To Serve Man: One of the larger fish almost eats Sadie while she was walking along the shore.
- Touched by Vorlons: The Crystal Landscape of Mask Island appears to have mutated mundane Earth wildlife to have bizarre mask-like faces, hence the island's name, and possibly made them stronger.
Animate, humanoid watermelons accidentally created by Steven. While they're loyal to Steven, they're loyal only to Steven, and treat everybody else as a potential threat (with the exception of Baby Melon). As of "Super Watermelon Island" they've formed their own tribal society. By "Escapism", they've splintered into separate tribes based on following Baby Melon or the Watermelon possessed by Steven that encouraged them to fight Malachite.
- Action Mom: One female Watermelon Steven adopts a baby melon with her husband, and is later seen going off to battle Malachite alongside her kin. She apparently became leader of the warrior tribe that split off.
- Bizarre Alien Reproduction: The adults grow their own children on Mask Island, just like how normal watermelons reproduce.
- Blood Knight: The plants created by Rose Quartz's Green Thumb abilities are described as "[living] to fight." The melons are no different, although this changes when they have time to make their own society.
- Carnivore Confusion: The Watermelon Stevens on Mask Island use the seeds from their dead to grow melon plants that produce baby melons, but also animals like the limbless Watermelon Chickens which rock back and forth. Apparently they taste like chicken to the Stevens.
- Character Development: In their first appearance, they were mindless mooks who get violent at anything they thought was a threat to Steven. Their second appearance has them as a more peaceful society who now think for themselves.
- Chekhov's Boomerang: Two seasons after they'd last been seen, Steven uses the Watermelon Steven to contact help while being held prisoner on Homeworld.
- Creating Life Is Unforeseen: Steven accidentally made them by spitting watermelon seeds around and leaving them to grow overnight.
- Game Face: They look like fairly harmless, featureless Steven-shaped watermelons most of them time, but when they're provoked, they open their previously invisible jaws and bare their teeth.
- Hair-Trigger Temper: They're violently protective of Steven to an incredible degree. Pearl simply laying her hands on Steven's shoulders is enough to provoke them.
- HeelFace Turn: In "Watermelon Steven" they're mostly antagonistic. They've become a lot nicer in "Super Watermelon Island", and even help the Crystal Gems fight Malachite with Steven's encouragement.
- Leitmotif: "Watermelon Steven", a retro-sounding piece. Uses more orchestral instruments in "Super Watermelon Island" to show how much more refined they've become.
- Logical Weakness: Being living watermelons, they suffer from some problems as a result of their source material. Their bodies wear out quickly since watermelons go bad in about two weeks, and a watermelon bird is unable to fly because its watermelon body is far too heavy.
- Ludicrous Gibs: They burst into watermelon slices when killed. The animators were specifically instructed◊ that the pieces be slices, not pulp.
- Made of Plasticine: They're fragile enough that they can burst into watermelon slices from hitting the ground too hard.
- Masculine Girl, Feminine Boy: When the Watermelon Stevens are going off to fight Malachite, there is a husband wearing a blue tie who makes sure to hug his pink flower-wearing wife before she leaves him to take care of their child.
- Planimal: In their second appearance, they are now living alongside Watermelon dogs, chickens, and horses. By "Escapism", we see non-domestic watermelon animals, including birds (which can't fly) and a large shark.
- Plant Mooks: Steven accidentally grew them by spitting a bunch of watermelon seeds around, which grew overnight.
- Poisonous Friend: These things see basically everything as a threat to Steven that needs to be destroyed. They grow out of it, though.
- Proportional Aging: In the few months between appearances, they go through several generations, and some have become elderly.
- Remote Body: In "Super Watermelon Island" Steven finds himself able to use Astral Projection to take control of a melon person as he's sleeping.
- Ridiculously Cute Critter: "Super Watermelon Island" shows they've learned to grow watermelon creatures as well, including a watermelon dog that Steven befriends. Even the watermelon shark is oddly cute looking.
- Roar Before Beating: Threaten Steven in front of them and they'll suddenly bare fangs and hiss before attacking.
- Significant Double Casting: Shares the same voice actor as Steven.
- Tertiary Sexual Characteristics: Some of them when they're on Mask Island; the females usually wear grass skirts and/or flowers, the males either have none or a tie. They've been abandoned by the time the tribes split apart, save the warrior tribe leader, who still wears flowers.
- Took a Level in Kindness: In their second appearance they've formed their own peaceful tribal society, and have a statue honoring Baby Melon.
- The Unintelligible: By the time they reappear, they've developed a language of growls past hissing.
- We Are as Mayflies: Inverted; as normal watermelons go bad in about 14 days, Word of God is that Watermelon Stevens have short lifespans.
- What Measure Is a Non-Human?: Despite being (nearly) sapient, none of the humans or gems treat the Watermelon Stevens' lives as very valuable. The Crystal Gems immediately smash them en masse when they start attacking Beach City, and Steven doesn't hesitate to possess one and push their body past the limit (dismembering and eventually killing them) for his own ends.
- Zerg Rush: They're individually fragile, but they're able to overwhelm the Crystal Gems and Malachite through sheer numbers.
Mechanical drones used by the Homeworld Gems. The small spherical repair drones are called "Flask Robonoids" and giant ones are called "Plug Robonoids". The conical Attack Drones are called "Shattering Robonoids".
- Attack Drone: The Shattering Robonoids fly around the nooks and crannies of Homeworld, seeking out dissident Gems to destroy.
- Call a Rabbit a "Smeerp": Consistently called "robonoids", never "robots". The latter term is foreign to Homeworld, and so Steven had to explain it to Peridot.
- Crippling Overspecialization: The Shattering Robonoids have no way of tracking Gems besides scanning their gemstones and are unable to detect anything that doesn't have a gemstone. Lars uses this to his advantage.
- Cute Machines: The Flask Robonoids are diminutive and seems to have some level of sentience and independence. Not as cute when they Zerg Rush Steven to shove him into space.
- Defeat Equals Explosion: The Shattering Robonoids blow up when destroyed, including the last one that was impaled by a rock. This seems to be because its Lightning Gun was damaged.
- The Dreaded: The Shattering Robonoids are feared by the Off Colors, since these drones are programmed to destroy them on sight.
- Enemy-Detecting Radar: Shattering Robonoids have scanners that seek out Gems. They ignore any other form of life, including full humans, even if they attack the drone.
- Floating Limbs: Flask and Plug Robonoids walk on rigid cylinders that float around their body which are also fully retractable.
- Healing Potion: Flask Robonoids dispense an unidentified substance that can repair warp pads. When a Robonoid is destroyed, it splatters everywhere.
- King Mook: The Plug Robonoids from "Marble Madness" are about three or four meters wide with a deeper shade of turquoise than the Flask Robonoids, and have six feet instead of four.
- Lightning Gun: The Shattering Robonoids fire a beam of electricity that causes explosions.
- Sinister Geometry: The Flask and Plug Robonoids consist of a single large sphere suspended between several cylindrical or domelike protrusions that act as limbs, making them seem alien even to the Crystal Gems. The Shattering Robonoids are floating cones with eye-like patterns on the bottom.
- A Form You Are Comfortable With: It takes Steven's form at the end of Attack the Light when told it doesn't have to be a weapon. This is defied at the end of Save the Light, where part of its decision to assert its independence is to dispense with any projection at all.
- The Farmer and the Viper: In the bad ending of Save the Light, Steven's advice for the Light to make their own decisions backfires. It decides they want to keep conquering worlds with Hessonite.
- I Have Many Names: Also known as the Light Prism, the Light Warrior, the Light Army, the Prism Monsters, the [Color] Light, Light Steven...
- Keystone Army: Creates and controls an army of Hard Light monsters.
- No Biological Sex: Not male or female, but more obvious about it than the gems, as the Light Prism and its creatures aren't nearly as human-like. It's also referred to as "it", and not in an insulting way.
- Not Evil, Just Misunderstood: It attacks in the first game because it considered Steven its master and mistook the other Crystal Gems for his enemies.
- You Are Better Than You Think You Are: The Light was created and lives to serve whomever activates the Light Prism as their weapon. But Steven, after activating the Prism himself, convinces the Light to live for itself as something other than a weapon.
Jungle Moon Aliens
The fauna of a jungle-covered moon orbiting a planet that was mined out by Homeworld. They're the first non-Gem aliens that we've seen.
- Bizarre Alien Biology: When the beetle-like alien is cut in half, the upper half sprouts legs and runs away while the lower half remains dead, implying only the former had vital organs.
- Bizarre Alien Locomotion: The giant bird blob rolls around like a wheel and can float through a Parachute Petticoat method.
- Cub Cues Protective Parent: A tiny bird blob that Stevonnie was conflicted whether or not to eat happened to be near its much larger parent.
- Parachute Petticoat: The bird-like alien can morph the flesh on its lower body into a skirt-like shape, and flaps it to float around.
- Starfish Aliens: The ones we see look like a dog-sized beetle, a hoofed, humped dinosaur, and a beanbag with a beak and talons on the end of tentacles.
- Super-Persistent Predator: While it wasn't trying eat them, the bird blob goes to great lengths to kill Stevonnie long after they had left its baby alone. It chases them into the moon base, and some hours later, it climbs onto the dome and starts pecking at the glass. It only leaves after Lars shoots at it.