Blessed with the ability to fly, Cosmo loves high places, and can dash across the sky so quickly that at night they're often mistaken for shooting stars. This has lead some people to treat them like lucky omens, making wishes whenever they spot one.
Once a Cosmo evolves, its body takes on a rather peculiar form. Its armor insulates it from incoming attacks while also allowing it to breathe underwater. Opinions on the Estrella's origin differ widely, but one master from a different world claimed Estrellas were commonplace where he was from, a claim with significant implications considering Estrellas are primarily found in Star Sanctuary.
After their evolution from Estrellas, Polarises are almost always seen riding an aircraft of unknown origin. The aircraft, which looks like a cup or bowl of some sort, is psychically connected to the Polaris, moving according to the Polaris's will. Should another Astromon or human try to board the aircraft, it will be unresponsive. A veil mystery shrouds this Astromon.
"You need to be extremely careful around dark Cosmo. Though they are able to grant people's wishes, they choose to do so in twisted, evil ways."
-Excerpt from "Potentially Educational Nighttime Stories"
"Some people say that dark Estrellas grants a person's wishes in horrible, sick ways, but that is utter hogwash. I have taken the liberty of collecting statements from respected Astromon researchers and providing them below. They all agree with my professional opinion that, though Estrellas do have certain psychic abilities, these abilities do not extend to granting wishes. The testaments of those claiming to have had a wish granted can easily dismissed as unfortunate coincidences. However, should you ever encounter a dark Estrella, it is advised you remove yourself from the situation as quickly as possible. Dark Estrellas are violently territorial."
-Excerpt from "Logic vs. Reality: Astromon Superstitions Debunked"
Dark Polarises are infamously fussy and nearly uncontrollable. It is often said they are as hard to raise as they are mysterious. To put that into perspective, the vast mojority of people will probably never see a dark Polaris in their lifetimes. And yet, Polaris have gained an unusual amount of notoriety, largely due to the autobiography of one of the most famous (on a number of levels) masters in all of Ultima, C. Brandon. In his book, he devoted an entire chapter to his love and hate for his Polaris, which was said to have struck fear into the hearts of all of Brandon's close associates due to its near constant mischief.