Vorlon

The Vorlons are a sapient, spacefaring species and one of the First Ones that evolved in the Milky Way Galaxy billions of years before the emergence of the younger races. While most of the First Ones left the galaxy long ago, the Vorlons and the Shadows opted to stay behind and influence the development of other species, using opposite methods that represent their opposite ideologies.

Biology
In the 23rd century, Vorlons are typically seen inside their encounter suits, their real appearance being a well-guarded secret, and the quarters of the Vorlon ambassador to Babylon 5 were filled with an alien atmosphere. This, however, turns out to have been an elaborate ruse on the Vorlons' part, as they can survive in an oxygen atmosphere without problem, and only use their encounter suits to hide their involvement with the historical development of other species.

As they acted as guiding figures to the younger races, the perceived appearance of a Vorlon depends on the observer. Different species will see a winged, luminous angelic figure with a head resembling that of the observer's own species. This isn't the Vorlons' actual appearance either, but only a telepathic projection. In their real form, Vorlons are indeed luminous flying creatures, but their appearance is far from humanoid, instead being tentacled, translucent and radially symmetric.

Vorlons are telepathic and psychically connected to each other, at least to some extent. They can detach parts of their consciousnesses and place them inside other organisms, allowing them to experience the world through their host's senses.

After Ambassador Kosh's death in 2260, Lyta Alexander claimed that it's been a long time since any of the Vorlons died.

Culture and society
When dealing with other species, Vorlons tend to be secretive and enigmatic, offering brief cryptic remarks that are rarely elaborated upon. Their spaceships are living organic constructs, controlled by telepathy. Their government is known as the Vorlon Empire.

The conflict between the Vorlons and the Shadows can be simplistically described as one of order versus chaos, as the Vorlons believe in guiding other species through discipline, whereas the Shadows believe that making species fight each other for survival brings better results. What started as merely conflicting philosophies eventually escalated to galactic wars with both sides willing to sacrifice entire races and planets to further their goals.

The Vorlons have also been responsible for tampering with the DNA of several species to create telepaths to be used as weapons against the Shadows.