FF Whisperin Core Development Materials A material used to break through weapons, ascend Resonators, and upgrade skills.

The Tacet Core of a special Whisperin. It takes the form of an intricate star, bearing both recognizable and unfamiliar Frequency Energy. It seems that humans only know the tip of the iceberg of themselves.
Sources
Synthesis - Purification
Synthesis - Transposition
Drop: Whisperins