Use 30 rectangle (1:2) and 60 square sheets of origami paper.
Difficulty : ⭐⭐⭐⭐
Time: 5 hours
 
It looks like spikes of sea urchin.
 
Model paper size:
Base (white) : 3.75 cm x 7.5 cm
Pocket (purple) : 3.75 cm x 3.75 cm
 
Model height: ~ 10 cm
 
PrwOrigami - Kusudama Collection
www.prworigami.com
(June, 2019)