[@Anndgrim]
Nullomancy is not the only form of magic and as an old player you should know that well, shame on you.

Under constantly changing conditions the most common denominator will be stored - kill a few thousand people of different races and eventually the only thing in common between them would be the etherial. Or go visit the god of the underworld and win them in a game of poker if you prefer. You should know this. Shame on you.

Sirens and other mythical creatures have their abilities completely unrelated to nullomancy or crystals. the swamp sirens put people to sleep to drown and eat them - you personally captured one and stored her call to use as a debuff on enemies in battle in the last RP. You know this, shame on you.

Yes, just keep it in your pocket in real life and it will charge that rather quickly. Or use any of the siren calls and mental control to instill that emotion and feeling like you know how to do. Shame on you.

and finally you know as well as I do that crystals do not filter out things, compound materials are stored as is. Hence the whole section on purity and isolating the precise thing/element/matter you want stored beforehand. Again Grim, you know this, shame on you.