[piytar]

Never sharpened, but the blade will wear down quickly. Sea urchins deal with this via replacement since they are alive. Blades? Not so much.

Now, make a living hardened steel blade that stays eternally sharp and grows to replace lost material, and we’re talking! Meanwhile, I’ll stick with hardened steel, high carbon steel, various alloys, and the like. And a good sharpener...

[muawiyah]

We can go a long way toward that design if you can devise a handle with a fishtank component where you can FEED the critter.

I'm going to name my new living sword "Bowser" ~

[HiTech RedNeck]

And you’d have to keep giving the critter something to chew upon, lest you open your kitchen drawer and find a monster overgrown knife in there some day.

[Sacajaweau]

Sharpening knives on a sanding block was a big deal at our house. It was just cool.