User blog comment:Plexioth- xD/Monster Hunter 3 Ultimate/@comment-83.160.18.226-20130405132854/@comment-1878425-20130405140224

Break his head; that gives you a shell with 30%. Then you can either catch him and get 1 shell with 42% chance or kill and carve him 3 times with 28% chance to get one each time.