The element lutetium was named after lutetia the latin name for Paris. It was almost simultaneously discovered by three different chemists.

The coat of arms of Paris contains stylised lillies, which the monster is based on.

Erbium is named after the swedish find spot Ytterby, just like Yttrium, Terbium and Ytterbium. Apparently the chemists of that time were not very creative in naming.

Therefore Erby is the third monster of the Ytterbies.

The name of this element comes from the Greek word dysprositos, meaning "hard to get" because it is literally hard to get.

Dyspro the moster therfore prefers to stay hidden.

This element was named after the finnish chemist  Johan Gadolin, who himself discovered a completely different element: yttrium.

Promethium was named after Prometheus, one of the titans of greek mythology, who brought fire to mankind. The gods then punished him by binding him to a rock in the Caucasus. There an eagle came every day eating his liver, which always grew back.

The name was chosen as a warning to humankind, since this element is radioactive as a product of decay of uranium. By the time of the discovery the nuclear arms race between the USA and the Sovied Union had begun.