gonna do all of them :)

Raiden's is an english version of Raijin, the god of thunder and lightning in Japanese mythology. "Rai"vbeing Thunder and "Den" being Lightning. As for why they chose it, it's because it was their father's name since he was a higashi born Draco!

Hati is based on the Norse mythological wolf who's paired with Sköll. Being a Lupo it's kinda fitting why i picked it. As for why they picked it? knowing Hati they probably picked it off some old scripts.

Cascade is based on the Cascade Waterfalls which is unorthodox for a Liberi but it fits how her tail and hair feathers are blue + they like water. But it also represents how fluid and adaptable they can be. Cascade didn't choose her codename, more over it was given to them.

tl;dr im a nerd and like using references to myths