Enelites

the Raiju are Mesozoic parasites that can live on/in any electrical sources and electronics, such as storm clouds, power lines, electric eels, ahuizotls and appliances.

Humans
Nero, as a electricity bender, can preform a Seiko with these via the brooch

History
in the beginning of the last Ice Age, early humans in the arctic spotted the shoulder fins of a Mature Raiju, sticking out of a pool, they ran away when it woke up and jumped out, suddenly, the Raiju calmed down and joined them.