How to get crystal of destroy

Guide of how to get crystal of destroy. One crystal of destroy can be transmute into 5 crystal of life (transmute it in Dr. X quest). There are two ways to get it :

1. Finish the last 2 quest in the vertex quest(you must beat 3 guard daily), if you can finish the vertex quest, you can earn 3 crystal of destroy.
2. Beast plain quest, random bosses give you crystal of destroy, such as exile, savegery, etc.

To do that, it's better if you have aigaaw, or wicked.