Radon the heaviest and at the same time the only radioactive noble gas. It is a decay product of naturally occurring uranium or thorium and dissolves out of the ground into the atmosphere, where it aggregates in caves or cellars. Even though the element is radioactive, it is supposed to have healing qualities. There are even official spas that offer radon baths as a form of therapy. The medicinal benefit is disputed.
Even though xenon is the rarest non-radioactive element on earth, it is used for many purposes, for example in xenon arc lamps, which are often found in car headlights. Its name is derived from the Greek word xénos, meaning "strange" or "foreign".
Argon is a noble gas. That means, it doesn’t form any compounds with other elements. Air naturally contains about 1% of argon. A scientist once calculated, that with every breath you breathe a few argon-atoms, that any person in the world has already inhaled before – alive or dead.
Argo the monster really lives up to his name: It means inert. So he likes to float lazyly around and meditate the whole day. Every once in a while he utters some very wise words.
Everybody knows helium from balloons. When inhaled it turns your voice into a squeaky high-pitched Mickey Mouse voice. It is completely harmless since the noble gas reacts with nothing and nobody. There is only verry little helium on earth but even the more in the sun.
Heli the monster is a dremy little dandelion clock. Oblivious to our every-day life it floats away and thinks about nothing...
When speaking of neon, everybody thinks of neonlight. But most of the „neon tubes“ contain mercury vapor. Neon glows red.
The name simply means „new“. So Neo the monster likes everything new and cool. He doesn’t like to get his hands dirty and prefers others to do the work.
Krypton is a very rare noble gas. It can be found in lamps, flashes and lazers.
Krypto the monster likes to keep hidden and spy on other monsters. Is he just a crazy stalker or does he have a secret mission?
Like the other noble gases he doesn’t have arms, instead he can move things by pure mindpower.