Planet of Origin: Gallaxhar's Planet, in the Milky Way Galaxy. A big, cold, pink earth-type planet, the first planet of his star system, the second planet being a big, blue, gassy planet that has a number of small rings. The star system of the planet includes only a single red dwarf which both planets revolve around.
Gallaxhar's are a blue skinned non-hmanoid species which developed an advanced space-faring civilisation. They standing from 2 to 3 meters tall on 6 long tentacles atthe tip of which are small 3 fingered handlike feet. The tentacles are attached to a somewhat humanoid body at the top of which is a head with four eyes, a giant cranium with a pair of sensory antenna on its top.
The Gallaxhars - whihc might have had another name - all perished when their planet was destroyed by one of them who came to be known as Gallaxhar. The date at which the planet was destroyed remains unknown but prior to 2009. Gallaxhar survived the destruction of his homeworld in his giant spaceship and put himself in cryogenic sleep while his ship's comptuer went on looking for Quantonium, a powerful radioactive energy source which he wants to use to clone himself into an army at his service. Gallaxhar was presumably destroyed when his ship exploded during an attempt to invade Earth in 2009.
Source: Monsters vs Aliens