body power
Size Manipulation
Also called Growth, Shrinking, Mass Alteration
Size manipulation changes the user's scale. Whether it is impressive depends entirely on what happens to mass: a character who shrinks while keeping full mass becomes a devastating projectile, while one whose mass scales with size is simply small.
How it works
The interesting version is conserved mass. Ant-Man at insect size still weighs what a man weighs, which is why a punch from him lands like a bullet. That single rule is what separates a gimmick from a threat.
Scaled mass users are proportionally strong when large and proportionally weak when small. Simple, and much less interesting.
Growth is where settings usually forget physics. Square-cube says a sixty-foot human collapses under their own weight, so any giant character requires an unstated durability upgrade — which is why the better-written ones have explicit limits or visible strain.
How it scales
- Scaled
Mass changes with size. Small means weak.
- Conserved
Mass stays constant. Small and devastating.
- Growth
Increases scale, usually with an unstated durability grant.
- Extreme
Sub-atomic or building scale, with a stated cost.
Who has size manipulation
Across 3 universes. This list crosses publishers — something no single wiki can do, because every franchise keeps its own separate database.
| Character | Universe | Franchise | Feats |
|---|---|---|---|
| Ant-Man | Marvel | Marvel Comics | 4 |
| Groot | Marvel | Marvel Comics | 2 |
| Hank Pym | Marvel | Marvel Comics | 3 |
| Mister Fantastic | Marvel | Marvel Comics | 2 |
| Ms. Marvel | Marvel | Marvel Comics | 3 |
| Beast Boy | DC | DC Comics | 2 |
| Clayface | DC | DC Comics | 2 |
| Elasti-Girl | DC | DC Comics | 3 |
| The Atom | DC | DC Comics | 4 |
| Choji Akimichi | Anime & Manga | Naruto | 4 |
| Nezuko Kamado | Anime & Manga | Demon Slayer | 2 |
The feat ledger
Every entry cites the work it comes from. Feat means it was shown in the work; Statement means a character or narrator said it. Nothing here is a fan estimate unless it is tagged Calc.
Ant-Man — Retains full human mass while shrinking, so a punch at insect scale lands with a man's momentum
The Atom — Controls his weight independently of his size, allowing him to be tiny and immovable at once
Choji Akimichi — Expands body mass at a caloric cost severe enough to shorten his lifespan at the highest tier
Groot — Grows from a sapling to building height within an engagement
Groot — Hardens to a density that turns aside heavy weapons at full size
Clayface — Expands to building height by absorbing surrounding material
Clayface — Splits into separate masses and recombines
Beast Boy — Takes forms far larger than his own mass, including a whale and a tyrannosaur
Beast Boy — Shrinks to insect size in the same engagement he grows to a dinosaur
Ms. Marvel — Embiggens a single fist rather than her whole body, her signature move
Ms. Marvel — Grows to building height at significant physical cost
Ms. Marvel — Shrinks small enough to escape a sealed container
Elasti-Girl — Grows to enormous height, her most-used ability
Elasti-Girl — Shrinks to inches tall in the same scene she grows
Elasti-Girl — Lifts weight proportional to her size rather than by separate strength
Choji Akimichi — Expands his whole body to many times normal size
Choji Akimichi — Enlarges single limbs for precision rather than his whole body
Choji Akimichi — The technique burns stored calories directly, which is why it leaves him emaciated
Mister Fantastic — Flattens to a sheet or thins to a thread, changing apparent volume
Mister Fantastic — Overstretching causes lasting injury, the stated limit on him
The Atom — Shrinks to subatomic scale and returns
The Atom — Controls weight independently of size, which is the ability's real trick
Ant-Man — Shrinks to insect scale using Pym particles
Ant-Man — Grows to building height using the same particles in reverse
Ant-Man — Enters sealed systems at reduced scale, his standard method
Hank Pym — Discovers the Pym particles that every other size-changer in the setting depends on
Hank Pym — Shrinks and grows within a single engagement
Hank Pym — Has used at least four separate identities built on the same power
The Atom — Shrinks to enter a human bloodstream and operate there
Nezuko Kamado — Changes her body size at will, from child-sized to adult
Nezuko Kamado — Shrinks small enough to be carried in a box during daylight
Limits
- Growth is constrained by the square-cube law unless a setting waives it.
- Shrinking without conserved mass is a stealth power, not a combat one.
- Extreme scale changes are usually time-limited or physically taxing.
- Most users depend on equipment — a suit or a substance — not biology.
Counters
- Attacking the equipment rather than the person.
- Area attacks against a shrunken user.
- Confined spaces against a grown one.
Questions
Why is Ant-Man dangerous if he is tiny?
Because he keeps his full mass while shrinking. At insect size he still weighs as much as a grown man, so his punches land with a man's momentum concentrated into a point. Size manipulation without conserved mass is a far weaker power.
Last updated 2026-09-06 · machine-readable version