Poly Puzzle

Hi Thingiverse :)

Today, I've got something really different.

Here is my puzzle game which seems to be easy, but this is really hard puzzle if you have no blueprint how to solve it.

Hope you'll have fun and do not suffer with it. Honestly I've tried to solve it without any help and I wasn't successful at all. -_-

Whole assembly is made of Fillamentum Timberfill colour pack and it looks really great and if you want to catch this colour combination please print it like that:
1-1; 1-2; 1-3
2-1; 2-2; 3-3
3-1; 3-2; 3-3
4-1; 4-2; 4-3

Thank you so much,
Antonín