SPOILER : Requiem's artifacts guide

[ThePhoenix]

It was one of the hardest...

Spoiler below!

I had to use 3 stone cubes and crumble 2 others to use their pieces in order to create a rudimentary staircase.
Took me 15 minutes to succeed without having the staircase crumbling under my feet...

Three? How do you stack three? I've stacked two so far but don't have the height to add a third.

EDIT: Hmm, could you explain the placement of the cubes and pieces?