Sun Creature

The Sun Creatures are a sapient hostile species which dwell at the core of the sun, and can travel to Earth by riding solar flares.

They are able to turn the sun red by unknown means, which has the effect of nullifying a Kryptonian's powers.

Biology
The Sun Creatures are amorphous beings with fiery bodies that look as if they were made out of flames. Despite living in the interior of the sun, they can ride solar flares and survive in the Earth's atmosphere, where they can fly and set objects on fire with their intense body heat. Even fireproof materials confer no effective protection against them.

The Sun Creatures themselves claim that their bodies are made out of hydrogen, with a temperature of one million degrees (scale unspecified), which allows them to penetrate fireproof materials. According to Superman, however, the Sun Creatures are made of nuclear energy. Whether or not that's literally true, it has been shown that the control rods of the Super-Mobile's nuclear power source can absorb the energy of the Sun Creatures and drive them off.

Appearances

 * Super Friends, s04e02, "Lex Luthor Strikes Back" (1979)