Clan Buffs

"In order to master a clan skill, a clan needs to accumulate special items related to raid bosses and have a sufficient reputation score."

Does anybody know what these items are and what raid bosses drop them?

Vastland Egg- A grade
Fake Life core- A grade
Soul of an angel - A grade
Dragons Heart - A grade
Skull of reaper - A grade
Tombstone of the Ruin - A grade
Cradle of Creation - A grade

Here are the Items as listed in a translation....names might differ now.