Hollow cubes

[Kickflip1993]

I´ve seen a Megaminx ana a 3x3 without core, but they can be twisted.
i don´t have a photo, but i think you will know what i mean
How can this be made?

 

[joey]

It is very difficult. No-one but the people who made them really knows the full details of how they work.

 

[Lotsofsloths]

I want one!!