Here it's 3 puzzles in one.
1 common core and 3 different sets of pieces to put around the common core.
A lots of rotations are required.
The difficulty increase with the 3 sets.
Here, you can find the links to select the 3 correct sets :Tronc commun 1 level : 220.127.116.11.1.3Tronc commun 2 level : 18.104.22.168.3Tronc commun 3 level : 22.214.171.124.4
You can also use the photos to select the 3 sets.