Kilaaks

The Kilaakians (キラアク星人, Kiraaku Seijen?, Kilaak Planet People) (in Destroy All Monsters, 1968) were a race of female humanoids from the planet Kilaak, which was said to be between Mars and Jupiter. The aliens invaded Monsterland and assumed control of the kaiju and resident scientists. Soon the monsters were attacking cities across the globe - Godzilla attacked New York, Rodan assaulted Moscow, Mothra invaded Beijing, Manda attacked London, and Gorosaurus destroyed Paris. Despite the military's efforts to stop them, the aliens remained unscathed until their base on the moon was destroyed by the rocketship, Moonlight SY-3. When humanity broke the kaiju from their control, the aliens pulled out their trump card - King Ghidorah. However, up against the combined might of Godzilla, Anguirus, Gorosaurus, Rodan, Mothra, Kumonga, and Minilla, Ghidorah was easily slain. Godzilla then destroyed the Kilaakians' base on Earth, ending their threat.

The Kilaakians attempted to conquer Earth in order to create a great scientific civilization, which they stated needed some death to create. The aliens thrived in high temperatures and were greatly susceptible to cold. When they were struck by low temperatures, they shed their human guises and reverted to their true forms: small, metallic worm-like creatures.

Aside from their mind control devices (that can enslave both humans and kaiju alike), they don't seem to have any great technology, though they do have forcefields that can't be penetrated even by bullets. Their flying saucers aren't much of a threat in and of themselves, but they have the ability to engulf their outer hulls in flames, burning anything the ship may touch. This mode is called a "Fire Dragon."