Cyclops: (deadpan, despondent and bored) ...I shoot it with my Optic Blast.
There are many superheroes out there. Some, like Batman, do their super-heroing using years and years of training their bodies, showing human capability to a remarkable extent, possibly with the help from a utility belt as well. Others are like Superman, having a whole grab-bag of superpowers that needn't even be remotely related in some of the extreme cases. Then, there are superheroes like Cyclops. Beast Boy. Static. The middle-roaders. The ones that only have one listed superpower, but which they sometimes have many uses for.
As you can guess, this trope excuses unmentioned Required Secondary Powers, since they often aren't a power in their own right, though the line can get a little fuzzy at times. Elemental Powers are a sub-trope of this. In a show with Cast Speciation, this can easily become What Kind of Lame Power Is Heart, Anyway?. (See Hawkman in the Superfriends cartoon.)
- The espers in A Certain Magical Index and A Certain Scientific Railgun generally seem to operate like this. They have one very specific power that they can use in all sorts of ways (eg. Misaka has control over electricity, which she can use to stick to walls, shoot lightning, create railguns...). The one esper who breaks this rule is Gunha Sogiita, who has several powers that don't seem to have anything to do with each other, frustrating researchers to no end, especially since he has no interest in learning how his powers work. Mages tend to be a bit more complicated.
- Contractors in Darker Than Black have only a single power. They might be creative with it, but it always comes back to one general ability.
- Most of the Wizards of Fairy Tail are only proficient in one type of magic, but can use that magic in many different ways. Erza has a full arsenal of magical weapons and armors she can summon, and Gray can make anything out of ice.
- JoJo's Bizarre Adventure gives us Stands, most of which have one ability (healing, stopping time, turning things into paper). The majority of a Stand user's strength comes from how flexible they are with these powers (for example, the Stand with "healing" as its ability can heal human wounds... and rebuild broken objects, and reconstitute meals into their component ingredients, and...).
- Devil Fruit from One Piece gives a person one super human ability. What regular humans can do in that universe would be super powers pretty much anywhere else though.
- Although many of the Devil's Fruit have multiple powers that all fall under one name. For example, the Sand Sand Fruit lets the user control sand, turn into sand, and drain water out of other people's bodies.
- The best example of this trope would have to be the protagonist himself, Monkey D. Luffy. He is a Rubber Man, able to stretch and contort his body like it was rubber. That's about it. He keeps discovering new and increasingly creative applications for it, however, that it's the only power Luffy needs.
- Similarly, most alter-users from sCRYed have one ability granted to them, at least at first. They may later get upgrades in power, and several characters have multiple largely unrelated abilities (Straight Cougar, for example, has the ability to make things fast, which manifests as super speed... and turning cars into pink supercharged vehicles). Main character Kazuma's only ability at the beginning of the series is an armored right arm.
- My Hero Academia usually works like this, with 80% of the human population being born with superpowers. While most people simply inherit a combination of their parents' Quirks note , a rare few get both, like Shoto Tororoki who possesses his father's fire powers and his mother's ice powers at the same time. The students at U.A. are trained to overcome this, learning to use their powers in different ways: protagonist Izuku Midoriya has a Quirk that enhances his body, which he initially just uses to give himself self-destructive Super Strength, but with experience he learns to spread the power evenly throughout his body, granting a lesser degree of strength but also exceptional speed; he also figures out how to use the force of his strength to launch concussive blasts of air.
- The series also goes into the possibility of someone gaining multiple powers, primarily thanks to All For One, which has the power to steal other powers and bestow them upon others. He used this to create the Nomu, individuals with multiple powers whose brains atrophied from the strain, turning them into mindless monsters. On the other side of the coin, All For One created his own arch-nemesis by bestowing a Quirk that stocks power to his supposedly powerless brother...who actually had a useless Quirk that he could pass on to other people. The two abilities combined into a single Quirk that gets stronger with time and can be passed on to others, creating One For All, the Quirk used by the hero All Might...and by Izuku.
- A significant number of characters from X-Men. Cyclops, Quicksilver, Magneto, Polaris, Rogue (even though she uses her one power to get many), Mystique, Shadowcat, and almost too many others to mention. In theory, all Mutants are supposed to have one and only one power, but this is not really the case.
- This is inconsistently applied to Nightcrawler. Sometimes teleportation is considered his only "true" power, with things like hiding in darkness being just a function of his dark fur and wall-crawling coming from his unusual fingers and toes (and he's therefore unable to cling to very smooth surfaces). Other times he has full-on invisibility in shadows and can climb pretty much anything.
- Daredevil. His only power is enhanced senses.
- From DC Comics, we have Wildcat, Dr. Mid-Nite, both Wonder Twins, Metamorpho...
- At the time he was created, The Flash's sole superpower was super-speed. However, he's since gotten a host of... very vaguely speed-related powers, turning the Speed Force into a Swiss-Army Superpower. For example, he has a healing factor (i.e. healing very fast), can time travel (albeit only with special equipment), can phase through walls and projectiles (vibrating himself down to the atomic level), drag someone into the Speed Force to kill/imprison them, drain all the Speed Force from an opponent to freeze them in place, and also perform an Infinite Mass Punch (basically hitting someone so fast it'd be as if he had Superman levels of Super Strength behind his blows).
- Similarly, the Hulk was originally just a very big, very strong behemoth. Soon, he gained an assortment of powers, some which were logical in relation to increased muscle ability, such as super-leaping, Nigh-Invulnerability, Super Speed and Super Reflexes. Then, over time, things just got crazy, and he gained other abilities such as immunity to mind control, ability to see supernatural creatures, ability to absorb radiation, a Healing Factor that rivals Wolverine's, a gland that lets him breathe underwater, and sometimes the ability to create new personalities as needed (each with their own power set).
- Replace "Superheroes" with "Anti-Heroes" and Cassie Hack of Hack And Slash now qualifies thanks to the recent arcs of her comic book series, because she gained a healing factor (literally her only genuine super-power at this point) since then.
- The pre-reboot Legion of Super-Heroes had a "No Duplicate Powers" rule. They accepted only one member with a particular power, and traditionally members had only one each- Cosmic Boy, Saturn Girl, Lightning Lad, Brainiac 5, Triplicate Girl, etc. There are some exceptions, like Superboy and Supergirl.
- In The Incredibles, most members of the Parr family have one superpower each (Super Strength for Bob, Rubber Man powers for Helen, Super Speed for Dash), and the film implies that is also the case with most supers. The exceptions are Violet, who has both invisibility and force field generation, and Jack-Jack, who appears normal but develops a wide variety of powers in the climax.
- Of course, Violet's powers are identical to Marvel's Invisible Woman, who originally only had the invisibility and developed the forcefields later. Helen is a gender-swapped Mr Fantastic, Bob's powers are equivalent to the Thing, minus the downside, Dash has Quicksilver's powers and Frozone has Iceman's.
- All superpowered characters in Sky High (2005) are like this outside of Will, who inherited one power from each of his parents (Flight from his mother, Super Strength from his father). Lampshaded by Royal Pain when Will's flight power manifests during the Final Battle.
Royal Pain: You're flying?! That's impossible!
- X-Men Film Series: Telepathy is Professor X's sole mutant gift, but it's a very handy one.
- In the Wearing the Cape setting, a significant percentage of breakthroughs are single-power types, loosely or tightly defined. Blackstone practices "stage magic" (illusions, levitation, teleportation), The Harlequin is bouncy to the point of physical invulnerability, Rush is "fast", etc.
- Witches from Charmed are usually born with a single unique "active" power along with their basic witch abilities. The Charmed Ones start this way (telekinesis, time-stopping and premonition), but subsequently develop new powers as advancements of their original powers. It's subverted with Paige. The prophecy dictates that she would gain the power of telekinesis, but also discovers that she possesses a whole set of other powers due to her Whitelighter lineage. Piper's children also continue this trend (also being half-Whitelighters) and possess even more powers than her aunt.
- Most superpowered characters in Heroes have only one power, and many others have "related" powers (eg Hiro Nakamura can bend time and space).
- Pretty much everyone on Misfits are only given one power by a mysterious storm. In the original gang, Kelly has Mind Reading, Curtis has Time Travel, Simon can turn invisible, Alisha makes people want to have sex with her, and Nathan is immortal. In the new group, Finn has telekinesis, Jess has X-Ray Vision, Rudy has a Literal Split Personality, and Curtis first switches powers to become a Gender Bender and later switches to raising the dead. Most of the other powered characters also have one power, and sometimes it's useless anyway (or seems that way).
- A lot of the supers in the Whateley Universe. Chaka can control ki. That's it. Except she can control her ki, your ki, pull extra ki out of the ground, read ki in other people, learn tricks by watching people use their ki... Blot can absorb electromagnetic energy. Kamuro can shoot sparks out of her hands.
- How to Succeed in Evil has this in characters mentioned off-hand by the narrator or the protagonist.
- In Worm, superpowers cover basically every type you could imagine, so naturally many individuals have just one specific power and maybe some Required Secondary Powers. That being said, even the most one dimensional powers tend to have a fairly wide variety of clever uses, and frequently in the series the bug-controlling protagonist realizes that control over all insects in a few block radius can actually applied for ''a lot'' of different effects. Some also have a single power that can produce a variety of effects, like Eidolon who's "single" power is the ability to switch between having a variety of other powers (although a limited number and for a limited time), and Lung who's ability can basically be summarized as "turning into a dragon when he's fighting" which includes rapid regeneration, pyrokinesis, super strength, flight and so on. There are, of course, lucky exceptions like Alexandria who simply have multiple distinct powers.