When there is a hero with some elastic abilities, he often makes moves that makes absolutely no sense in regard of the laws of physics.

But a man named Joe is not able to avoid them. Having his body recently fused with a strange material with excellent elastic properties, Joe must now abide by the following conditions :

  • Elastic material always acts as it should be : Force is proportionnal to the distance of elongation (even negative elongation).
  • Conservation of mass. This limits the range of stretching, up to 10 times the regular size. Over this limit, plastic deformation occurs, and damage is done to the extended bodypart

In order to be able to keep a secret identity, Joe can solidify his bones at will (to make them as solid as normal bones)
It would be possible to solidify on an extended limb, but it would become spontaneously more fragile.

Joe hasn't got any experience with advanced combat techniques, he learnt on his own to keep his balance when throwing punches and kicks, and that's pretty much all about his training as a new superhero.

How efficient would he be in combat against armed thugs (with brass knuckles, bats, guns, etc...) ?

  • 4
    $\begingroup$ I just had to say: is this hero called The Eraser? $\endgroup$
    – JDługosz
    Apr 23, 2016 at 4:33
  • 3
    $\begingroup$ I don't know, I based myself on a more realistic (downgraded) version of M.D. Luffy. $\endgroup$ Apr 23, 2016 at 13:20
  • $\begingroup$ Isn't he a bit like Mr. Fantastic? $\endgroup$ Apr 23, 2016 at 17:35
  • $\begingroup$ Luffy strikes again! $\endgroup$
    – pojo-guy
    Apr 26, 2018 at 20:16

3 Answers 3


I'm not good enough at physics to run the numbers on this, but if I were Joe, I'd develop a fighting style that took advantage of the whip-like properties of my limbs. Whipping motions significantly increase velocity at the point of impact, and make for attacks that are difficult to predict, and which can get around an opponents guard. A rigid blunt weapon like a club would essentially gain the benefits of a flexible weapon without the disadvantages (think nunchacku, or a meteor hammer).

Flexibility is also a significant part of the physical conditioning component of martial arts training, so Joe would get a freebie there. He'd still have to practise the manoeuvres, but he wouldn't need to expend the time and effort getting into shape. Also, while Aify's answer already addresses the resilience to blunt trauma, Joe would also have a huge edge in grappling, which no-holds-barred hand-to-hand combat tends to devolve into: no fear of limb locks or breaks, plus the ability to literally tie up an opponent with his own arms and legs. He could still be pinned by sheer mass, I suppose, but I wouldn't like their chances, since he'd be able to extend a limb or two and turn the tables from beneath regardless, and again, wouldn't be "tapping out" due to pain/discomfort. Can he still be choked? Since there's a minimum diameter his neck can compress to, I would assume so, but at least he doesn't have to worry about his vertebrae.

  • $\begingroup$ Interesting. I won't try to dig the biologic stuff (blood pressure, breathing capacities, etc...), but I like the fact that he can either keep a distance while swinging a heavy object, or lock their enemies in direct contact. $\endgroup$ Apr 23, 2016 at 13:34

For a real-world application of the 'rubber man', I'd say look at the octopus. A tentacle can extend many times its original length, move in any direction, and is phenomenally strong. The limbs of a boneless human could probably work the same way, however the ability for the torso or especially the head to stretch would probably be much more limited - squishing organs, especially the brain or the heart, is not very healthy.

The superhuman resilience of the rubber man in fiction doesn't seem very realistic - a rubber band doesn't get hurt when you punch it, but that's because a rubber band isn't alive. Boneless animals, by contrast are quite vulnerable to blunt trauma (there's a reason why octopuses tend to be shy).

If Joe has the ability to solidify his bones at will, he might want to keep his skull and ribcage intact while fighting, because one good punch to an unprotected brain or heart could easily kill him. This will limit his flexibility (no wrapping his enemies up like a snake) but is probably worth it.

While an octopus or squid can 'shoot' their tentacles quite fast to grab a target, they don't generally use them for 'punching' so it's unclear whether Joe will be able to properly deliver a Gum-Gum Pistol. If he keeps his hand bones intact, though, he might be able to deliver a nasty punch by swinging his fist like a flail instead.

It is also worth noting that the strength of a tentacle weakens as it stretches. This is less of a problem in the water, but on land Joe might have problems with his limbs going floppy. He probably won't be able to walk upright without leg bones, let alone do that 'stretchy jump' that is so popular with superheroes like Mr Fantastic. Joe's ability to fight will rely heavily on his ability to strategically harden and soften his bones.

He'll be a monster at grappling, though. The added flexibility will offer a lot of advantages even without stretching, and he can even go the opposite way and make his arms stronger by compressing them.


This depends on what you define as "efficient".

Joe pretty much won't be hurt by brass knuckles, bats, or metal pole strikes - Try punching a rubber band; it won't do anything. He's pretty much invulnerable to hand held blunt force weaponry.

A gun, however, or a knife slash for that matter, can still do some considerable damage. I would treat him as a normal human when taking hits from sharp weaponry/firearms.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .