I'm reading a comic set in a really unique fantasy game. One of the creatures that really caught my attention were a type of slime/sword called ego sword. In their normal form they're a blob but can turn into innumerous items like swords, shields, etc. Here are some drawings I made of them (couldn't get pictures from the comic): blob form sword form shield form

So, without magic being the explanation, would ego swords be possible in our world? How would they harden and change form quickly? Could they be usable in battle, and could a body really be able to do that? What would be the drawbacks?

  • 2
    $\begingroup$ Soft robots and memory shape alloys come to mind. However, I can't tell if that can make a good enough sword. $\endgroup$
    – Theraot
    Jun 9, 2019 at 3:57
  • 1
    $\begingroup$ I think starfish can harden at will, but I am not sure. $\endgroup$ Jun 9, 2019 at 4:38
  • 1
    $\begingroup$ @Renan they can indeed harden at will, however a hardened starfish is only about as strong as bone. magical nanomachines might be the best choice. $\endgroup$
    – John
    Jun 9, 2019 at 12:57
  • 1
    $\begingroup$ An ego sword is an awsome concept. $\endgroup$
    – AlexP
    Jun 11, 2019 at 4:23
  • 1
    $\begingroup$ I see someone else has read Hardcore Levelling Warrior. $\endgroup$
    – IT Alex
    Jun 11, 2019 at 13:31

2 Answers 2


Possible, but only if they were non-homogeneous.

I'm going to work off the assumption that these are living beings. I've not an idea how such a living being would develop. So, let's discuss the Ego. This Ego would be more of a colony, rather than an entire unique organism, composed of a few different types - muscle, form, mind, and sight. (Types of what? Cells, maybe, or groups of supercell clusters.)

Muscle - these types let the Ego move. They're responsible for the blob form being able to move, and would allow it to shift shapes. Unfortunately, they'd be a bit lackluster, and wouldn't be able to give the Ego itself much strength. They'd also be reliant on the form cells to give them structure in blob form.

Form - these types are the hard parts. Literally. In blob form, they're dispersed as widely as possible, only linking with each other in rare thin, structures to allow the muscles to move the blob, than shrinking. In sword and shield form, they'd turn into the edges. (This gives you the advantage of having a sword that had a flexible middle, letting it take blows well.)

Mind - these types let the Ego give commands, telling the muscles to move around, letting the blob move and shift, and shift back from sword/shield to blob. Also dispersed, but they'd always be connected to each other, like a really flexible massive nest of nerves.

Eyes - the only single type, which lets the Ego see.


The egoes are made out of pure muscle, where muscles could harden or soften at will. The muscles are extremely small and thus flexible. They are arranged in an egg like pattern and thus have a slimy feel to them. Alternatively, muscles could be inherently slimy. Their eye is flat, having bad eyesight making them require wielding rather than combat, and is connected by extremely flexible nerves.

  • 1
    $\begingroup$ That explains their shaoeshifting, but how would they harden so much that they would be usable in combat? $\endgroup$
    – Onix
    Jun 9, 2019 at 14:18
  • $\begingroup$ And what exactly is a slimy muscle? $\endgroup$
    – Onix
    Jun 9, 2019 at 14:21
  • $\begingroup$ @Onix Muscles could be hardened in the human body, and what matters is their tinyness. The muscles could be incredibly tiny so that the weapon is extremely sharp. At the same time, muscles may be hardened so that they could be as strong as bone, from John in the comments. Slimy feel means it is part sticky and part smooth, and feels like liquid. Muscles in the human body satisfy that so the ego could have muscles like that. $\endgroup$
    – Aphrodite
    Jun 13, 2019 at 9:30

You must log in to answer this question.

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